A bomb blamed on the Tamil Tiger rebels ripped through a passenger bus in the heart of Sri Lanka's capital Tuesday, but no one was seriously hurt because the conductor saw a suspicious package and evacuated the passengers in time, the military said, AP reported Military spokesman Brig. Udaya Nanayakkara blamed the Tamil Tiger rebels, who have made bombings bus and trains a hallmark of their 25-year separatist fighting for the blast. He said the bus conductor and the driver, who noticed an unattended parcel, evacuated the passengers and took the bus to a less crowded area before the bomb exploded. The blast ripped off the rear of the bus. Dr. Hector Weerasinghe of Colombo National Hospital said that four people were admitted for minor injuries. The blast came a day after Sri Lankan President Mahinda Rajapaksa ruled out negotiations with the rebels, saying the military would soon destroy the rebel group and end the country's long-running civil war.