PRAGUE, Czech Republic -- Czech police are investigating a man for selling T-shirts featuring a portrait of Norwegian mass murderer Anders Behring Breivik, saying they appeared to endorse terrorism.

Police spokeswoman Kamila Harastova says a 26-year-old suspect in the southeastern city of Breclav sold some 30 t-shirts on the Internet. They included slogans such as "It was self-defence."

Breivik killed 77 people in twin attacks last year in Norway's worst peacetime massacre. He showed no remorse and accused his victims of betraying Norway by embracing a multicultural society.

Harasova said Tuesday an unspecified number of the T-shirts were seized.

If tried and convicted of approval of a criminal act could face up to one year in jail. He was not named.