Romanian prosecutors said Monday they had seized a refinery held by Kazakhstan's KazMunaiGaz, which recently came under Chinese control, in a tax fraud probe.

The seizure of the Petromidia refinery in eastern Romania is part of an investigation into tax evasion, money laundering and fraud.

KazMunaiGaz is accused of failing to settle debts contracted by former Petromidia owners Rompetrol which KazMunaiGaz took over in 2007.

"The prosecutor's work is ongoing," Mihaela Porime, a spokeswoman for Romania's anti-organised crime investigation unit, DIICOT, told AFP.

Seized assets at the refinery total 3 billion lei (660 million euros, $752 million).

Chinese group China Energy Company Ltd said last month it was acquiring 51 percent in KazMunaiGaz.

KazMunaiGaz managers are to be questioned in Bucharest on Tuesday over the debt accusations, the spokeswoman said.

KazMunaiGaz has been the target of several court actions over the Rompetrol debt dating back to 2001 and estimated at $570 million including compound interest.

KazMunaiGaz promised to pay $200 million to settle the cases, but has not actually paid out any funds, according to the Romanian government.