The human rights group Amnesty International says it has received reports that a breakaway rebel group in Sri Lanka is abducting refugees who are fleeing their homes to escape fighting in the region. As Anjana Pasricha reports from New Delhi, the government says the reports are not true.

Amnesty International says it has reports that armed groups are infiltrating overcrowded refugee camps in Sri Lanka's eastern Batticaloa district and abducting residents.

In a statement citing what it calls reliable sources, the group says that men wearing uniforms of the Karuna group are roaming the camps, and even distributing relief goods. The statement did not cite any numbers, nor say what has happened to the alleged victims.

Amnesty cites the example of a 15-year-old boy who was approached by armed men in a van who tried to drag him away while he waited for a bus. Unlike others, Amnesty says, he escaped.

Other rights groups have also spoken of abductions by the Karuna group. In January, New York-based Human Rights Watch charged that Karuna fighters were forcing hundreds of children and young adults to serve as soldiers. The activists allege that Karuna fighters appear to act with complicity of the authorities.

The Sri Lankan government strongly denies the allegations. Defense Ministry spokesman Brigadier Prasad Samarasinghe says only government security forces have access to camps.

"Karuna faction or any other faction, for that matter nobody will be able to abduct anybody from the refugee camps," he said. "Strict instructions have been given to all the security force ground commanders as well as to the police personnel who are providing security to the internally displaced camp, not to allow anybody to abduct or take by force anyone. Nobody can go [into the camps] with weapons and uniforms."

Brigadier Samarasinghe says any problems that might have taken place would have occurred while the refugees were fleeing areas still controlled by ethnic Tamil rebels, who are involved in violent battles with government troops.

The Karuna group split from the main Tamil Tiger rebel group in 2004, and has since clashed repeatedly with the rebels. It has a strong presence in the east, where its commander, whose name is Karuna, is based.

In the last week, more than 40,000 civilians have fled the latest bout of fighting between the military and the rebels. The fighting is taking place in the east, where the government has launched a fresh offensive to dislodge the rebels from their last major base.

The country's civil war erupted in 1983, when the rebels began fighting for a homeland for the minority Tamil community in the east and north of the country.