Justice Department officials are trying to seize more than $70 million in assets — including a Malibu mansion and Michael Jackson memorabilia — owned by the playboy son of the dictator of Equatorial Guinea.

Prosecutors filed civil forfeiture complaints against Teodoro Nguema Obiang Mangue and moved to seize a variety of valuables, including a 2011 Ferrari 599 GTO worth $533,000, collectibles and clothing valued at $1.8 million that were once owned by pop star Michael Jackson, a $38.5 million Gulfstream G-V business jet, and a house purchased for $30 million on 12 acres of property in Malibu, Calif.

In complaints filed or unsealed Tuesday, prosecutors alleged that Nguema used his position as a government minister to plunder more than $100 million from the African nation through “extortion, misappropriation, embezzlement, or theft of public funds.”

Nguema — son of President Teodoro Nguema Obiang Mbasogo, who came to power in a coup in 1979 — receives a salary as a government forestry minister of less than $100,000 a year, the Justice Department said.

“While his people struggled, he lived the high life,” Assistant Attorney General Lanny A. Breuer said. Attempts to reach a spokesman at the Equatorial Guinea Embassy were unsuccessful. The family has denied corruption allegations in the past.

The action is the largest effort to date by the Justice Department’s Kleptocracy Asset Recovery Initiative, created this year to target and recover the proceeds of foreign corruption laundered through the United States.

“This should keep suspected kleptocrats with assets in the U.S. awake at night,” said Robert Palmer, a spokesman for the nonprofit Global Witness. The nonprofit claims credit for exposing Nguema’s mansion overlooking the Pacific Ocean in Malibu in 2006.

“This is positive, but is it going to take five years to recover any of the other dictators’ assets?” Palmer said.

The civil complaints come as the United States weathers criticism for the pace of its search for assets belonging to the families of the deposed dictators of the Arab Spring. In an interview in Cairo last month, Hasham Gaafar, a senior attorney in the Egyptian prosecutor’s office, said Swiss and United Kingdom authorities have been more responsive to Egypt’s request to freeze and seize assets of former president Hosni Mubarak.

Gaafar said U.S. officials “are not meeting our expectations.”

Breuer said he could not comment on the Egyptian request. But he noted that kleptocracy cases are difficult and time-consuming because prosecutors must meet a high bar in showing that stolen assets were acquired through corruption.

“We are by far the most robust and active law enforcement partner in the international community,” Breuer said. “That doesn’t mean it is going to happen overnight.”

The Equatorial Guinea matter was exposed by the U.S. Senate’s Permanent Subcommittee on Investigations, which in 2004 found that Riggs Bank in Washington held millions of dollars in laundered Equatorial Guinea assets. Riggs pleaded guilty in 2005 to failing to report suspicious transactions and was fined $16 million.

The complaint details various spending sprees by Nguema, including a crystal-encrusted glove ($275,000) worn by Jackson during his worldwide “Bad Tour” in the late 1980s; three trademark fedoras worn by the pop star ($162,000); a pair of crystal-covered socks ($80,000); and a basketball signed by both Jackson and Michael Jordan ($245,000).