Libyan revolutionary forces escalated offensives Friday into two key strongholds of Muammar Qaddafi's rule, but met stiff resistance from snipers and loyalist gunners in Qaddafi's hometown and a mountain enclave where a pro-regime radio station urged followers to fight to the end.

The assault on Qaddafi's Mediterranean birthplace of Sirte and the strategic mountain town of Bani Walid appeared to be a coordinated campaign to break the back of regime holdouts. The attacks came as powerful revolutionary backers from the West and Muslim world urged on the anti-Qaddafi forces.

Turkish Prime Minister Recep Tayyip Erdogan joined Friday prayers in the heart of the capital Tripoli a day after the French and British leaders traveled to Libya. Supporters of Libya's interim government have stepped up calls to establish legitimacy and start rebuilding the country even as Qaddafi remains on the run and his followers try to hold their ground.

In Sirte -- the hub of a loyalist belt across Libya's central coast -- revolutionary units pressed their attack on two fronts with convoys that include vehicles mounted with anti-aircraft guns. Loyalist responded with sniper attacks and rocket barrages.

Smoke rise from parts of the city, where the green flags of Qaddafi's regime flew from mosques and buildings. The Misrata Military Council, which is coordinating the revolutionary offensive, said anti-Qaddafi forces had control of the old airport on the western edge of Sirte.

NATO warplanes swept overhead, but is was unclear whether there were fresh airstrikes to help the anti-Qaddafi advance.

The military alliance said it struck multiple rocket launchers, air missile systems, armored vehicles and a military storage facility in Sirte on Thursday when revolutionary units launched the offensive.

Abdel Salam, a fighter on the frontline near Sirte, said his side lost 11 men late Thursday when their bus drove over a roadside bomb. He said at least 18 fighters were detained by Qaddafi loyalists after they were ambushed at the entrance of Sirte.

"We reached inside Sirte and then retreated," Salam said before anti-Qaddafi forces mobilized a stronger offensive Friday.

About 150 miles to the west in Bani Walid, revolutionary fighters using pickup trucks mounted with heavy weapons tried to break through strong defensive lines. Explosions and gunfire reverberated across the area.

One of the fighters, Hisham Nseir, said the frontline is "very heated and chaotic" and his troops were meeting with heavy resistance from Qaddafi's men.

Commander Abdullah Abu-Asara told The Associated Press that his men were just over a mile from the heart of Bani Walid, which is ringed by mountains and only accessible through a valley that is watched over by pro-Qaddafi marksmen.

As the revolutionary forces advanced, the fighters erected the new Libyan flag over an abandoned electricity building and a military headquarters in the northern part of Bani Walid.

Around the buildings lay a huge Qaddafi poster bent in half and torn billboards with pictures of the ousted dictator. The walls were still sprayed with graffiti reading, "Long live Muammar."

Anti-Qaddafi forces also took strategic mortar positions, firing shells at the central square in Bani Walid that include a Qaddafi residence built on the former site of an Ottoman-era fort.

"Today is the first day that we have completely taken over this part of Bani Walid," said fighter Abul-Asara. "We are staying here."

Inside the town -- about 90 miles southeast of Tripoli -- a radio station believed linked to one of Qaddafi's main propagandist kept up a steady stream of appeals to fight and rants that demonized the revolutionaries as traitors against the country and Islam.

"Run from Bani Walid and you run straight to your graves," shouts one man over the radio.
Another portrayed the revolutionaries as trampling Muslim values.

"These revolutionaries are fighting to drink and do drugs all the time and be like the West, dance all night," the announcer claimed. "We are a traditional tribal society that refuses such things and must fight it."

On a third front, British warplanes conducted airstrikes Thursday in and around Sabha in Libya's southern desert, including a military vehicle depot used by pro-Qaddafi units.

Maj. Gen. Nick Pope, a British military spokesman, said a dozen missiles were fired on a "large concentration of former regime armored vehicles" that had been located by NATO surveillance.
As battles intensified, Libya's interim leadership has been pushing forward with efforts to form a new government.

Erdogan was greeted at the airport by Mustafa Abdul-Jalil, the head of the National Transitional Council, the closest thing Libya has to a government. He traveled to Libya as part of a tour of the Arab world, including Egypt and Tunisia, that is aimed at offering help for the countries and advancing his growing status as a regional leader.

He was expected to discuss how to resume investments in Libya, where Turkish contractors were involved in 214 building projects worth more than $15 billion before the rebellion that ousted Qaddafi.

Erdogan's tour comes as once-strong ties between Turkey and Israel are unraveling due to Israel's refusal to apologize for its raid on a Gaza-bound flotilla that killed nine pro-Palestinian activists last year.

The flotilla incident and Turkey's desire to broaden its influence in the Middle East and the Arab world could dramatically affect the power dynamics in the region since the revolutions now known as the Arab Spring.

Turkish companies have been involved in lucrative construction projects worth billions of dollars, building hospitals, shopping malls and five-star hotels in Libya before the uprising began in mid-February.

The bilateral trade with Libya was $2.4 billion in favor of Turkey before the chaos and the two countries had waived travel visas to boost that trade.

The United States and more than 30 other nations formally recognized Libya's main opposition group as the country's legitimate government in a July meeting in Istanbul, giving the rebel movement a major boost. The move came after Turkey escalated its pressure on Qaddafi despite its long-standing ties to the Libyan leader.

Erdogan has said that Qaddafi ignored calls for change in Libya and instead preferred "blood, tears and pressure against his own people."

Turkey has recently reopened its embassy in Tripoli which was shut down due to deteriorating security. The Turkish consulate in the rebel-controlled city of Benghazi remained open throughout the conflict.

Turkey initially balked at the idea of military action in Libya, but as a NATO member it is helping to enforce an arms embargo on Libya and volunteered to lead humanitarian aid efforts.