Libyan strongman Muammar Gaddafi is playing "dirty games" and trying to divide tribes in the besieged western city of Misrata, a military official and rebels said on Sunday.

"Gaddafi is playing a really dirty game," the rebel Transitional National Council's military spokesman, Colonel Omar Bani, told AFP.

Salvos of Grad rockets exploded and automatic weapons were fired on Sunday on Misrata in an apparent contradiction of the regime's claims its troops halted operations in the port city to allow tribes to solve the conflict.

"It is a trick, they didn't go," Bani said.

"They have stayed a bit out of Tripoli street but they are preparing themselves to attack again."

Tripoli Street, one of the main arteries of Libya's third city, has been left in rubble by shelling and heavy fighting, according to residents who have fled the violence and journalists.

Bani said Gaddafi was now putting prisoners plucked from the East of Libya and the Western mountains of Misrata on the streets of the city, arming them with Kalashnikovs and other weapons but no ammunition.

"The people in Misrata will think they are the troops of Gaddafi," he said, adding: "If they don't kill them, the soldiers (of Gaddafi) will kill them from behind."

Bani said Gaddafi had used a similar strategy in earlier Misrata battles by mobilising students from the military academies "too young" to cope with or understand the politics of the violent conflict.

"We captured many of them. They were crying saying we don't know anything about this war," he said in reference to troops captured by the rebels in Misrata, adding they had been released and sent back to their families.

He said Gaddafi was trying to create a "huge problem between the tribes of Libya from East to West," and "trying to show the world" that the tribes of Misrata were still with him.

Gaddafi "wants to prove that it is a civil war between the tribes of Libya, but this is not the truth. It will never happen," said Bani.

"Do you think I would fight against my family? It is impossible."

A vast number of families in Libya have been split by front lines and, left without news of their relatives, many are concerned that they have been killed or captured in the conflict.

"The tribes will not fight each other, everyone has relatives from East to West, how could they turn on kin?" said a rebel guarding the Western checkpoint of Ajdabiya at the weekend.

On Saturday, Libya's third city suffered the worst toll in 65 days of fighting, with 28 dead and 100 wounded compared with a daily average of 11 killed, according to Doctor Khalid Abu Falra at Misrata's main private clinic.

"Gaddafi always speaks and then does nothing," said another rebel stationed west of Ajdabiya when asked about the contradiction between Tripoli's words and actions in Misrata, where he has relatives.

"You should never believe what he says. He has lied for 41 years."

Libyan deputy foreign minister Khaled Kaim said early on Sunday the Army had suspended operations against rebels in Misrata, but not left the city, to enable local tribes to find a peaceful solution.

"The armed forces have not withdrawn from Misrata. They have simply suspended their operations," Kaim told a news conference in the capital.

"The tribes are determined to solve the problem within 48 hours. We believe that this battle will be settled peacefully and not militarily."

But bursts of continual automatic weapons fire could be heard as Grad rockets exploded on the city, the scene of deadly urban guerrilla fighting for weeks between rebels and Gaddafi forces.

Kaim had previously announced that the Army would withdraw from Misrata and leave local tribes to resolve the conflict in the city, either by talks or through force.