Jakarta - Indonesian authorities in Papua province released one of four Dutch journalists detained for allegedly violating immigration laws, an immigration official said Wednesday.

Elske Schouten, the NRC Handelsblad newspaper's Jakarta correspondent, was released overnight but the three others were still not allowed to leave the province, said Raden Hendiartono, the head of the Jayapura immigration office.

"The three were still under intensive questioning to determine their status," Hendiartono said by telephone from Papua's capital, 3,800 kilometres north-east of Jakarta.

"If there is enough evidence, they may be charged with violating immigration laws and could face up to five years in jail and pay a fine of 25 million rupiah," or 2,125 dollars, he said.

The three were confined to their hotel rooms in Jayapura while their passports were temporarily confiscated by the immigration office, he said.

Dutch international radio Wereldomroep confirmed that the trio worked for it as freelancers.

The journalists were arrested Tuesday while reporting from Jayapura on a demonstration by about 1,000 protesters in favour of a referendum on Papuan independence outside the provincial parliament.

The three had violated the regulation on using tourism visas for working, Hendiartono said, adding that they had filmed without permission.

"They should have asked for permission from the authorities on their news reporting activities prior to the news coverage," he was quoted as saying by the state-run Antara news agency.

Hendiartono said the journalists were in Papua to follow Nicholas Jouwe, co-founder of the pro-independence Free Papua Movement, who returned to Indonesia Sunday after more than 40 years in exile in the Netherlands.

Papua was a Dutch colony and remained one after 1949 when Indonesia gained independence. In 1961, an elected government prepared the region for full independence, but Indonesia invaded and precipitated a brief war with the Netherlands.

The United Nations intervened, and Papua was handed to Indonesia in 1962 and formally annexed seven years later after a referendum that Jakarta was accused of manipulating.

A small insurgency against Indonesian rule in the impoverished province has been conducted ever since. About
100,000 Papuans have died in military operations. Last week, suspected rebels attacked a security post, killing a government soldier. (dpa)