Margaret Thatcher's Son Arrested

South African police arrested Mark Thatcher, the son of former British Prime Minister Margaret Thatcher, early Wednesday on allegations he was involved in a plot to overthrow the government of Equatorial Guinea, police said.

Police spokesman Sipho Ngwema said Thatcher was arrested at his Cape Town home and is expected to be charged with violation of the Foreign Military Assistance Act.

"We have evidence, credible evidence, and information that he was involved in the attempted coup," said Ngwema. "We refuse that South Africa be a springboard for coups in Africa and elsewhere."

Police raided Thatcher's home in the upscale suburb of Constantia shortly after 7 a.m. Wednesday, armed with search warrants.

Thatcher was in custody at his home Wednesday morning as investigators searched his records and computers for evidence.

Investigators said they believe Thatcher assisted in a plot to overthrow the government of Equatorial Guinea.

"We believe Mr. Thatcher assisted in finance and logistics," said Ngwema, who declined to elaborate.

Equatorial Guinea plans to put 19 people on trial there, accused of involvement in the alleged plot. One other defendant died in custody under suspicious circumstances. Seventy other accused mercenaries are on trial separately in Zimbabwe in connection with the same alleged plot.

Equatorial Guinea has alleged that Thatcher and British and South African oil broker Eli Calil and other foreigners helped fund the alleged coup attempt. Lawyers for Thatcher and Calil have denied the allegation.

Thatcher is expected to appear in the Wynberg Magistrate's Court later Wednesday.

Ngwema said Thatcher was in his pajamas when police arrived.

The South African Press Association said police said Thatcher was being "relatively cooperative" with investigators.

By Elliott Sylvester