South Africa hosted an emergency meeting of regional leaders to negotiate a peace deal for Lesotho on Monday, following an attempted coup and stalled peace talks between deadlocked political parties.

South African President Jacob Zuma and Zimbabwean President Robert Mugabe - chairman of the 15-member Southern African Development Community (SADC) - will sit down with Lesotho's leaders to hash out a solution after rival party leaders failed to patch up their differences.

"For now we are very confident that this summit will help us to move forward on a number of issues," said Zuma, opening the meeting.

"One of the current issues of course is the current situation in the kingdom of Lesotho," he said, voicing optimism for a resolution.

"Part of the reason I am saying we are optimistic," says Zuma, "is because we want Lesotho to get back to normalcy as soon as possible."

On August 30, an attempted coup by renegade general Tlali Kamoli saw the military assault several police stations, prompting the prime minister to flee the country.

Prime Minister Tom Thabane has since returned, protected by South African guards, but a Pretoria-brokered peace deal quickly disintegrated after he refused to reopen parliament.

Reopening the legislature - which was shuttered in June - is seen as a key step toward restoring normality in the tiny mountainous state.

In Maseru, the political crisis appears to be intensifying.

A coalition of opposition parties has joined forces and called on the ruling tripartite coalition to reopen parliament, which is likely to result in an immediate vote of no-confidence for Thabane.

Politicians also rallied behind Kamoli.

The renegade general has refused a prime ministerial order to resign and has apparently raided government armouries in preparation for a showdown.

His allies have warned of a "bloodbath" if he is forcibly removed.

"The whole thing is a bit of a chicken-and-egg situation," said defence analyst Helmoed Romer Heitman.

"I can see the point he is reluctant to reopen parliament while there is a risk of his family being attacked; on the other hand there is no military solution to the problem," said Heitman, speaking from Pretoria.

"You can't solve a political problem with a military solution," he said. "You can enforce something for a while, but it can't last forever."

Heitman said it is unlikely that South Africa will send in troops to Lesotho. "I don't see South Africa putting in troops unless they are pretty certain a political solution is to follow," he said.

A military intervention would not be welcome in Lesotho, where many are traumatised by the events of 1998, when post-election violence prompted South African troops to intervene with SADC approval.

Police said Monday that they have launched a criminal investigation into the August 30 events, according to Maseru Police District Commissioner Mofokeng Kolo.

The military assault killed one officer at police headquarters in Maseru, injured nine others, caused significant damage to two other stations, and police were "robbed" of nearly four dozen automatic weapons, Kolo said.

The dead officer, Sub-Inspector Mokheseng Ramahloko, was reportedly guarding the armoury.

"We believe justice must be done," Kolo told AFP. "We believe these acts were illegal and a criminal offence - and we shouldn't keep quiet about them."

He rejected calls for an amnesty, which supporters say could help end the crisis.

"We can even talk about amnesty before reconciliation," Kolo said. "And we can't talk about reconciliation while we're still in the middle of this situation."