Thai police are attempting to identify a dismembered body found in a freezer after they raided an apartment and arrested three men - two thought to be American and one British - suspected of trafficking in forged passports.

Forensic experts will conduct a digital autopsy using a CT scan and extract DNA material from the body found in the raid in an effort to identify it, a police spokesman said.

The body was chopped up into six pieces and frozen for months, according to Dr Triyarith Temahivong, deputy director general of Thailand's Central Institute of Forensic Science.

"The body still has human tissue stuck on it, which DNA can be extracted from," he said. "The teeth can be used as well for identification through dental records, but the person's nationality, age or gender can't be determined at all at this time so we'll see from the digital autopsy."

Police have contacted the FBI in the US and Interpol for assistance.

The police spokesman said officers are also uncertain of the identities of the three suspects because they had multiple passports that could be fake or altered.

They were arrested on charges of resisting arrest, illegal possession of firearms and ammunition, forging official documents and concealing a corpse.

"We're trying to figure out the nationalities of the suspects with the embassies now, we simply know that they're all foreign nationals," police said.

Police said the suspect thought to be British shot and wounded a police officer during the raid and then was wounded himself.