Irish Prime Minister Brian Cowen, shown March 29 in Brussels, was unhappy over nude paintings of himself sneaked into two prestigious galleries. (Thierry Charlier/Associated Press)

An artist whose nude paintings of Irish Prime Minister Brian Cowen were snuck into two prestigious galleries was questioned by Dublin police on Thursday.

Irish guerrilla artist Conor Casby has reportedly handed over a series of satirical sketches to Irish police.

The furor over Casby's paintings of Cowen, which turned up mysteriously in the Irish National Gallery and the Royal Hibernian Academy, has ignited a debate over censorship and artistic freedom in Ireland.

One painting shows Cowen fully naked holding a pair of blue underpants in one hand, with the painting ending at his waist, and the other shows the prime minister sitting on a toilet with a roll of toilet paper in his hand.

In a statement to Irish media, Casby confirmed he had painted the pictures, saying they were a comment on the use of the modern media.

The galleries involved took down the paintings as soon as they were alerted to them — but the media had a field day with the satirical images.

The prime minister's office has come under criticism after phoning broadcaster RTE and demanding an apology for a news item on the paintings.

The opposition said the office was practising censorship and accused the police of overreacting.

"The public interest will not be served by a national broadcaster bowing to political pressure," said Liz McManus, a Labour Party representative. "We live in a democracy where political satire is part and parcel of our democracy."

Police also threatened to raid the offices of a local radio station after Casby spoke on air.

Police said the issue is still under investigation, but Casby could face charges of incitement to hatred, indecency and criminal damage.

Casby, 35, has handed over images of other Irish politicians, including former prime minister Bertie Ahern and Michael McDowell, the former justice minister.

A Dublin newspaper is reporting that someone was apparently caught on closed circuit TV hanging the paintings on the walls of the galleries without the use of nails.