MOSCOW -- Moscow police have detained a member of Ukraine's parliament as he was taking part in a march mourning a slain Russian opposition figure. Ukraine's parliament has protested the detention.

The federal Investigative Committee said Alexei Goncharenko was being questioned Sunday about his alleged involvement in a fire that broke out last year in his home city Odesa between pro-Ukrainian and pro-Russian demonstrators. Dozens died in the fire, including some Russian citizens.

The speaker of Ukraine's parliament, Volodymyr Groisman, said the detention was a violation of international law because Goncharenko has diplomatic immunity. The speaker urged Ukrainian Foreign Minister Pavlo Klimkin to take urgent measures to have the parliament member released.

For many Russians, the Odesa fire remains one of the more painful episodes of the Ukraine conflict.