Sri Lanka's Defense Ministry is accusing aid agencies of supporting the Tamil rebels and trying to prolong the island's civil war for economic gain.
The ministry says on its Web site Tuesday that local and international human rights groups, aid agencies and free media have made the Sri Lankan conflict a lucrative business.
The statement says the groups, including CARE International, want to ensure the war does not end, to ensure their continued income.
CARE International said last week that one of its local workers was killed in a "no-fire" zone in the conflict zone.
Sri Lanka says the person killed was actually a hardcore Tamil rebel who was planted in the aid agency, perhaps with the knowledge of its officials.
CARE has not responded directly to the accusation.
The stinging attack on humanitarian groups comes as Sri Lanka's military faces increasing international criticism about its conduct in the war.
A new report from the New York-based Human Rights Watch says the military is indiscriminately shelling the "no-fire zone" where thousands of civilians are trapped by the Tamil rebels.
The government denies the charge, and the rebels say they are not trapping any civilians.
The United Nations estimates that 150,000 civilians are trapped in the war zone, but Colombo says the numbers are unsubstantiated.
Some information for this report was provided by AFP and AP.