US troops in southern Iraq detained and beat up two public RTP television journalists from Portugal travelling in the company of two Israeli colleagues after accusing the four of spying, the RTP news director said today.

The four men entered Iraq on Monday in a jeep heading for the front.

They arrived at Karbala on Wednesday, but had to return to Najaf because the two Israeli reporters - public television correspondent Dan Scemama and Boaz Bizmuth, who works for the daily newspaper Yediot Aharonot - reportedly had no proper accreditation.

Near Najaf the four slept next to US tanks after refusing to quit the Israelis.

"When they woke up they were surrounded by military police pointing their guns at them," said RTP news director Jose Rodrigues dos Santos.

Luis Castro and his cameraman Victor Silva are well and now staying in Kuwait, dos Santos told Lusa news agency.

Castro was kicked around and Silva was brutalised, he added. They were held inside a jeep for 36 hours, accused of spying and forbidden to contact anybody until they were freed by an officer.

Scemama told his network they had spent the worst 48 hours of their lives during their detention.

"The American soldiers said we were terrorists and spies and treated us as such ... in spite of our explanations they threatened us for hours with their arms," said Scemama.

The four were not given any food and were taken by helicopter to Kuwait, where they received medical treatment.

Dos Santos said US officials later apologised and promised an investigation.

The Portuguese television network had not announced their disappearance, so as not to alarm their families.

Pentagon spokesman Lieutenant Colonel Dave Lapan said the journalists were "unilaterals" who "showed up on the battlefield and posed a security threat to forces there".

"The forces didn't know who these people were. They were told by headquarters to get them out of Iraq and back to Kuwait, which they did," he said, adding that the journalists were flown out in a military helicopter.

"We don't have any indication they were mistreated, but we continue to look into it," Lapan said.

US Navy Lieutenant Commander Charles Owens, a spokesman for US Central Command in Doha, Qatar, said the military was looking into the incidents and took such allegations seriously.

Agence France-Presse