MOGADISHU, Somalia — A pair of explosions rocked Somalia’s capital and left 11 people dead, the country’s police chief said Saturday, as the al-Qaida-linked extremist group al-Shabab claimed responsibility. Another 25 people were wounded, Gen. Bashir Abdi Mohamed told reporters in Mogadishu. He said the first car bomb went off near a security checkpoint for the presidential palace and was responsible for nine deaths. The second car bomb killed the driver and his accomplice near a checkpoint on the road to the heavily fortified airport, he said. Al-Shabab, which often targets the capital, said the blasts were meant to strike the first line of security checkpoints for the airport and palace.