Cape Town, South Africa ? P.W. Botha, the apartheid-era president who led South Africa through its worst racial violence and deepest international isolation, died Tuesday. He was 90.

Botha died at his home on the southern Cape coast at 8 p.m., according to the South African Press Assn. “Botha died at home, peacefully,” Capt. Frikkie Lucas was quoted as saying.

The African National Congress issued a statement expressing condolences and wishing his family “strength and comfort at this difficult time.”

Nicknamed the “Old Crocodile” for his feared temper and sometimes ruthless manner, Botha served as head of the white racist government from 1978 to 1989.

Throughout his leadership he resisted mounting pressure to free South Africa’s most famous political prisoner, Nelson Mandela. Mandela was released by Botha’s successor, F.W. de Klerk in 1990.

Although Botha liked to depict himself as the first South African leader to pursue race reform, he tenaciously defended the framework of apartheid, sharply restricting the activities of black political organizations and detaining more than 30,000 people.

Through a series of liberalizing moves, Botha sought support among the Asian and mixed-race communities by creating separate parliamentary chambers. He lifted restrictions on interracial sex and marriage. He met with Mandela during his last year as president.

But after each step forward, there was a backlash, resulting in the 1986 state of emergency declaration and the worst reprisals of more than four decades of apartheid.

The meeting with Mandela was one of Botha’s last acts before he was ousted as National Party leader by de Klerk in September 1989.

Within a year after Botha left office, de Klerk released Mandela after 27 years in prison and put South Africa on the road to its first all-race elections in 1994, when Mandela became president.

In December 1997, Botha stubbornly resisted appearing before a panel investigating apartheid-era crimes. He risked criminal penalties by repeatedly defying subpoenas from the Truth and Reconciliation Commission to testify about the State Security Council that he headed.

The council was believed to have sanctioned the killing and torture of anti-apartheid activists, and the panel wanted to know what Botha’s involvement was.