president declared a state of emergency Saturday after her foreign minister was assassinated at his home. The military blamed the Tamil Tiger rebel group, which the slain official worked to ostracize internationally as a terrorist organization.

Lakshman Kadirgamar, 73, was shot in the head and heart at about 11 p.m. Friday. He was rushed to the National Hospital where he died, hours after he delivered a speech to a group of students on international relations.

"The minister had just returned from a swim and was getting inside his home when he was shot," Inspector General of Police Chandra Fernando said. He said there were two snipers hiding in buildings near Kadirgamar's heavily guarded home in the capital's diplomatic district.

Authorities began house-to-house searches in the area and made two arrests at a neighboring house.

President Chandrika Kumaratunga declared a nationwide state of emergency Saturday to "facilitate enhanced security measures and effective investigations of this act of wanton terror," her office said.

As dawn broke, dozens of military trucks moved in and soldiers took up positions at major intersections in the capital.

The emergency law, used at the height of the conflict between the government and the Tamil Tigers, allows authorities to detain without trial anyone suspected of involvement in terrorist activities.

Kadirgamar, a member of the ethnic Tamil minority himself, was a close aide to Kumaratunga. The Oxford-educated lawyer led an international campaign against the Tigers, who remain on terrorist lists in five countries, including the United States and Britain.

The Tamil Tigers began fighting in 1983 for a separate homeland for ethnic Tamils in the country's north and east, claiming discrimination by the majority Sinhalese. The conflict killed nearly 65,000 people before Norway brokered the cease-fire.

Government soldiers stand guard outside Colombo's National Hospital, where Foreign Minister Lakshman Kadirgamar was taken for treatment after the attack at his home.