A bomb exploded on a bus parked near a crowded Bombay railway station Monday, killing at least two people and injuring 26 others.

The bus was empty when the explosion occurred, but shrapnel from the bomb hit bystanders, killing two people, police said.

"Police suspect it was a crude bomb. They are investigating," said Kripa Shanker, junior minister for home affairs of Maharashtra state. Bombay is India's financial hub.

Police said the bomb apparently was placed under a seat in the rear of the bus, which was parked near the rail station. Witnesses said the back of the bus was demolished.

"We heard a loud explosion and everyone began running away. I saw the back of the bus blown off," said Ismail Sheikh, a fruit vendor, who lay in hospital bed, his hands covered in bandages.

There was no claim of responsibility, Bombay's top police official said.

"It is too early to identify any group. The impact of the explosion was quite severe, which is why people nearby were injured," said Police Commissioner N.N. Singh.

"Most people who were brought in from the site of the explosion had injuries in the head or limbs. These have been caused by splinters. Most of them are still in shock," said Dr. Abhay Desai.