MISRATA, Libya (Reuters) - Rebel forces have routed most of Muammar Gaddafi's troops in the Libyan oil town of Brega in the biggest boost of their campaign in weeks, spokesmen said on Monday. The government denied the claim.
More than 40 people on both sides were reported killed in fighting over the city since late last week.
The rebels have encircled Brega, an oil export terminal with a refinery which for months marked the eastern limit of Gaddafi's control, said spokesman Shamsiddin Abdulmolah.
But its streets were strewn with landmines, making it hard to secure full control of the area.
"The main body (of Gaddafi's forces) retreated to Ras Lanuf," which lies to the west, he said by telephone from the eastern rebel stronghold of Benghazi.
However, government spokesman Moussa Ibrahim said that, "our brave soldiers and volunteer soldiers are in Brega in their thousands and control it completely."
"NATO and the rebels have tried to attack Brega for the last five days," he told foreign journalists in the capital Tripoli. "The only way for them to control Brega is to attack it with nuclear bombs."
He said the government had lost 30 soldiers over five days of fighting, but rebels had lost many times more. Abdulmolah said 12 rebels were killed and some 300 wounded on Saturday and Sunday.
Most rebel forces were now past Brega and heading west toward the towns of Bishr and Ugayla, he said.
While rebel fighters have been making gains in eastern and western Libya in recent days, Russia criticized the United States and other countries for recognizing the rebel leadership as the legitimate government of Libya, saying they were taking sides in the insurgents' five-month-old war to oust Gaddafi.
"Those who declare recognition stand fully on the side of one political force in a civil war," Foreign Minister Sergei Lavrov told reporters in Moscow.
Secretary of State Hillary Clinton announced U.S. recognition of the rebels on Friday, a major diplomatic step that could unblock billions of dollars in frozen Libyan funds.
Russia and China have taken a softer line toward Libyan leader Gaddafi, and neither attended an international meeting on the conflict in Turkey on Friday.
Brega, about 750 km (465 miles) east of Tripoli, has a strategic oil terminal. The attack could signal a new rebel push westwards after weeks of stalemate.
It has changed hands several times in the back-and-forth fighting along Libya's Mediterranean coast since the rebellion began in February.
Libyan TV, in a bid to counter the rebel claims, showed what it said was footage taken on Monday in Brega. Students were shown taking an exam, and there were pictures of the port, oil terminal and a worker at a natural gas plant in the city.
Rebels say taking Brega will this time be a tipping point in the conflict on the eastern front.
"It is going to take the revolutionaries at least 10 days to claim full control of Brega," said rebel spokesman Abdelsalam in Misrata.
Gaddafi is refusing to step down despite the five-month-old rebellion against his rule, a campaign of NATO air strikes, and the defections of members of his inner circle.
The slow progress of the rebel military campaign has caused strains within NATO, some member states pressing for a negotiated solution to hasten the end of a conflict some thought would last only a few weeks.
Reports have circulated that Gaddafi is seeking a negotiated way out of the crisis, but on Saturday he called the rebels worthless traitors and rejected the idea he was about to leave the country.
NATO said it had on Monday struck an antenna radar system, which was being used for military purposes at Tripoli's main airport. Naji Daw, acting director of civil aviation at the airport, told journalists the target had purely civilian use.
NATO warplanes have also been attacking pro-Gaddafi forces near Brega. The alliance said targets hit on Friday included one tank, five armored fighting vehicles and two rocket launchers.
On another front, in the Western Mountains region southwest of Tripoli, pro-Gaddafi forces exchanged artillery fire on Sunday with rebels in the village of Al-Qawalish, a rebel fighter manning a checkpoint there told Reuters.
A rebel spokesman in the regional town of Zintan said rebels had repelled a bid by Gaddafi troops to enter the town.
Additional reporting by Lutfi Abu-Aun in Tripoli, Steve Gutterman in Moscow, Yasmine Saleh and Omar Fahmy in Cairo, Peter Graff in Al-Qawalish, Libya, Joseph Nasr in Berlin and Hamid Ould Ahmed in Algiers; Writing by Richard Meares; Editing by Myra MacDonald