By Charles Haviland BBC News, Colombo

Authorities say nearly 6000 former Tamil Tigers are yet to be released

They say some have been taken back in for police questioning after being released.

But they say the numbers are not great and that the process of releases is continuing.

The army says more than 11,000 Tamil Tigers surrendered and were taken into military custody in the war’s final stages.

The circumstances are controversial. The International Committee of the Red Cross has had no access to those who surrendered.

The army has been putting them through a process it calls rehabilitation.

'Arbitrary questioning'

And the officer in charge of this, Brigadier Sudantha Ranasinghe, has now told the BBC that half of them – about five thousand six hundred – have been released in batches since early last year, returning to their home areas.

	ICG had received reports that some of those freed have been subject to arbitrary questioning

Yet there have been rumours that the release process has not always gone smoothly.

The Brussels-based International Crisis Group says it has had worrying reports that some of those freed have been subject to “frequent and arbitrary questioning” by the security forces.

Brigadier Ranasinghe says that in some places they have indeed been taken in for questioning, but says it is not because of their past but because of complaints from villagers that released former Tigers have been committing crimes such as stealing or brewing illicit liquor.

He was not able to give details but said they were not being held for long.

Sources in eastern and north-western Sri Lanka confirmed to the BBC that some ex-combatants have been questioned in this way.

In 2009 a former LTTE member in a rehabilitation camp told the BBC that he feared his home community in central Sri Lanka would not accept him once he left detention.

'De-radicalisation'

The Geneva-based International Organisation for Migration is the only big international agency working to help reintegrate the ex-fighters. It said last month that the former Tigers were being treated quite well.

Brigadier Ranasinghe said the ongoing rehabilitation programme included what he called “de-radicalisation” and “mentorship” as well as skills training.

He said clinical psychologists were involved in the work in the rehabilitation camps.

The government says 700 of the original surrendees are detained in a special facility and will face legal action rather than being rehabilitated.

It says about 4,600 are still undergoing “rehabilitation”. Brig Ranasinghe was unable to give a timetable for their eventual release but he said they would contine being freed in batches.

Rights groups based overseas allege that their detention violates international legal standards.