(CNN) -- Fighting battered the outskirts of the Libyan city of Misrata and shelling resounded in the besieged city's port Tuesday.At least three people were killed and 14 injured when shelling by Libyan leader Moammar Gadhafi's forces hit a tent of refugees at a Red Crescent camp, according to hospital sources and Marie Colvin, a foreign affairs correspondent for the Sunday Times of London who is in Misrata. The three dead were from Niger.
"I was out at a nearby clinic when the port was hit, and the men from Niger were brought in badly injured. One died there, two were blown to pieces at the camp. Three dead total. I went out to the camp after that. Tents were still on fire. Missile parts buried in sand," Colvin said.
Shelling could be heard in the area of the Misrata port, with a couple of pops per hour ringing out. A strike was heard coming from the direction of Misrata, possibly from a NATO plane, and large explosions were felt, witnesses said.
A Misrata port security officer told CNN that there has been shelling on the wider Misrata port and that says that "refugees located between the steel port and the main port have been targeted."
A CNN crew saw some plumes of smoke rising from an area beyond the Misrata port, and another TV crew said it saw fire in the distance "earlier."
But Misrata residents told CNN that the smoke and fire is actually coming from Tawargha, a town about 21 miles away from the port. The residents also say that the Gadhafi troops are currently positioned in the area of Tawargha.
Jean Michel Monod, who heads the International Committee of the Red Cross delegation in Tripoli, said a ship that was in Misrata to pick up foreigners had to depart earlier than anticipated in the morning because there was shelling very close to the port area and it was too close for comfort.
He said there were about 630 people on the ship, and it was pretty much full. The capacity is 600 to 700, and he said the ICRC would have liked to take on a few more people.
Street fighting and confrontations between pro- and anti-government forces erupted in Misrata's suburbs and pro-Gadhafi forces miles away struck the city, a witness said.
However, the witness said, the city center is calm. There's no street-to-street fighting in the urban cauldron and Tripoli Street, the city's main boulevard, is clear, the witness said.
Misrata has been the scene of some of the deadliest battles of the war as rebels attempt to oust Gadhafi, who has been in power for more than four decades.
Hundreds of people have been killed in the battle for the city, which has been under siege by Gadhafi's forces for seven weeks. Its population of about 450,000 makes it the country's third-largest city.
"As fighting continues to rage in Misrata, the families recently evacuated by boats to Tobruk from the embattled city describe a catastrophic situation with many having lived in fear of indiscriminate shelling. Many houses and buildings have been destroyed and some families had to move several times," the U.N. refugee agency said Tuesday.
The U.N. High Commissioner for Refugees said parts of the city have lacked electricity and water and people have been hiding in their homes for two months "before seizing the opportunity of a lull in fighting to get to the harbour and board a boat."
"Sniper fire, street clashes and shelling have prevented people from venturing outside of their homes to get food and medicine," the agency said.
"In some neighborhoods in Misrata, pregnant women gave birth in their homes as it would have been too dangerous to make the trip to the hospital."
The U.N. refugee agency also said about 30,000 Libyan civilians have fled the fighting to Tunisia from their homes in the western mountain region in recent weeks.
NATO is leading an international military operation in Libya that includes airstrikes targeting Gadhafi's military resources. It is operating under a U.N. Security Council resolution authorizing all means necessary to protect civilians.
State-run Libyan TV reported that "Libya officially calls on Russia to ask for an extraordinary session by the Security Council to discuss the continuation of the crusader colonial aggression in bombing Libyan civilian locations and its attempt to target the leader Moammar Gadhafi ... violating the two council's resolutions and the international conventions and laws."
In Copenhagen, Denmark, Russian Prime Minister Vladimir Putin was critical of the Western coalition.
He said at the beginning the coalition didn't want to kill Gadhafi, but now, he said, some officials are acknowledging he's a target.
"At first, they spoke about the need to close the air space. All right, but how does that correspond with bombings of Gadhafi's palaces every night?
"They say they don't want to eliminate him. But why are they bombing his palaces then?" he asked.
He also said he dislikes the relentless pounding of a small country and the destruction of its infrastructure.
"Initially there was talk about imposing a no-fly zone. But now we're seeing the country's entire infrastructure being destroyed, and one of the warring sides is now advancing, protected from air. This can go on and on forever," said Putin.
"I think that we should act within the framework of international law, understanding our responsibility and with care towards the civilian population."
U.S. National Security Council spokesman Tommy Vietor reiterated Tuesday that the NATO mission is to enforce "the arms embargo, no-fly zone, and conduct a civilian protection mission," but it's not regime change.
"As part of that mission, the coalition has targeted command and control sites that are being used by regime forces to wage attacks against Libyan civilians -- brutal attacks that this week alone have reportedly killed dozens of civilians in Misrata alone. In fact, the degradation of those sites is part of the reason the opposition has had increased success in pushing Gadhafi's forces out of Misrata in recent days. There is no change in U.S. policy regarding assassination."
British Foreign Secretary William Hague, briefing the House of Commons on NATO's operation in Libya, said "the case for action remains compelling" and that Gadhafi has shown "he has no regard for civilian lives."
"By his actions it is clear that Gadhafi has no intention of observing the conditions in Security Council resolution 1973 that I described to the House earlier this month," Hague said. "He has repeatedly ignored the cease-fires that he himself has announced. Our military action is defined by the U.N. Security Council resolutions. We are also clear that Gadhafi should go and it is impossible to see a viable or peaceful way forward for Libya until he does so."
He said diplomatic, economic, and military pressure against the Gadhafi regime has been successful. He said military action has "seriously degraded" Gadhafi forces and they remain unable to enter Benghazi, where the opposition is based.
Hague said he is looking forward to the report from the International Criminal Court on crimes against humanity by the Gadhafi regime, and he said there will be another meeting of the international Contact Group on Libya May 5 in Rome.
CNN's Raja Razek, Reza Sayah, Saad Abedine and Joe Sterling contributed to this report
