Mr Premachandra was shot dead in Mulleriyawa on Saturday allegedly by a rival SLFP group

12 pistols, two revolvers and two T-56 automatic rifles have also been arrested regarding the shooting in which a presidential advisor was shot dead, police said in a statement.

The statement comes after lawyers in a Colombo court accused the police of not arresting the real culprits who murdered at least three people in Mulleriyawa.

Describing the arrest as "ironic," the lawyers accused the police of arresting "innocent" workers in the Colombo suburb.

The comments came in Colombo magistrate's court as police produced six people on suspicion of trying to cause unrest after the killing of a presidential advisor and at least two others.

Knife found

Presidential advisor on trade unions, Bharatha Lakshman Premachandra and at least two others were shot dead allegedly by supporters of defence ministry advisor, Duminda Silva revealing a bitter internal rift within the ruling party.

	'It is clear that this was carried out using illegal firearms'

In a report submitted to the court on Monday, Mulleriyawa police said of evidence to suggest that the six suspects have tried to cause unrest in the area by stoning houses after the shooting.

A knife that has been in the procession of the suspects was also found, the police said.

The Colombo magistrate rejecting the police request to remand the six suspects in custody released them on bail.

Defence spokesman Lakshman Hulugalle, however, told BBC Sandeshaya that there was no violence in Mulleriyawa at all following the shooting.

However, a police curfew was imposed in the area on Saturday.

A senior minister in the government who described the incident as "unfortunate," meanwhile, has admitted that the shooting seems to be a result of a "power struggle" between two factions of the ruling United People Freedom Alliance (UPFA).

State media

"It is clear that the killing of Bharatha Lakshman Premachandra was a result of using illegal firearms," Chief Government Whip Dinesh Gunawardena told BBC Sandeshaya.

Doctors are happy about the outcome of the successful surgery Dr Ravindra Gamage, Sri Jayawardene hospital

The minister said the government will take all necessary action to investigate the usage of illegal firearms by the government politicians.

Nearly a thousand supporters of Mr Premachandra, meanwhile, have protested in Kolonnawa wearing black bands against the murder.

They urged the president to arrest the killers and take appropriate action.

Duminda Silva MP, who also received head injuries, is still being monitored on life support machine after a successful surgery, Dr Ravindra Gamage, the director of Sri Jayawardenapura hospital, told BBC Sinhala service.

"Doctors are happy about the outcome of the successful surgery," Dr Gamage added.

Mr Silva is the monitoring MP for the defence ministry and a close associate of President Mahinda Rajapaksa's eledest son, Namal, MP.

The BBC's Charles Haviland in Colombo says that the state media have largely ignored or sought to play down the bloodshed.