Indian police Thursday are questioning a married couple in connection with Sunday's train bombing that killed 68 people.

Security officials say they detained the husband and wife late in Bikaner in northern Rajasthan, an area bordering Pakistan.

Media reports say the man resembles the sketch of a suspect released earlier this week.

There are conflicting reports about the number of people who have been detained in the ongoing probe, with figures ranging from three to 12.

Also Thursday, Indian authorities transferred the bodies of 12 Pakistanis killed in the attack to their relatives in Pakistan. Pakistani soldiers carried the coffins across the border and passed them to grieving relatives.

The bombing took place on a train from New Delhi to the Pakistani city of Lahore. Two small bombs aboard triggered a fire that engulfed the train about an hour after it left the Indian capital.

Some information for this report was provided by Reuters.