Prosecutors charged two former aides of Japanese Prime Minister Yukio Hatoyama on Thursday with giving false reports about political funding, a serious embarrassment for his new government.

Hatoyama, who has repeatedly denied any wrongdoing, immediately called a news conference and apologized for the scandal. Prosecutors said the prime minister will not face any charges.

Former aides Keiji Katsuba, 59, and Daisuke Haga, 55, were indicted for violating laws on political funds, a prosecutors' statement said. The allegedly falsified reports involved nearly 400 million yen ($4.4 million) in contributions.

"I feel a deep responsibility," Hatoyama said at the hastily called press conference at a Tokyo hotel.

The scandal has dominated recent Japanese media coverage and cast doubts about the new government of Hatoyama's Democratic Party, which took power in September. The parliamentary election win ended the rule of the Liberal Democrats that continued almost uninterrupted since World War II.

The two former aides are accused of listing dead people as donors to hide where political money came from, as well as underreporting some donations, according to the prosecutors.

Some of the donations related to the charges came from Hatoyama's mother and older sister, prosecutors said in a statement.

Hatoyama hails from a rich family, and his grandfather was a former prime minister.

The charges are another blow to Hatoyama, who has seen support ratings for his government fall gradually after the parliamentary elections that swept him to power.