NEW DELHI -- Investigators have prepared a sketch of a suspect they want to question over the three deadly bomb blasts that shook India's financial hub Mumbai, police said Sunday.
The drawing composed from eyewitness accounts would be circulated among officials investigating the blasts but would not immediately be released to the public, a police official said on condition of anonymity as he was not authorized to speak to the media.
Meanwhile, a man picked up by police for questioning in connection with the blasts died Sunday in Chembur, a Mumbai suburb. Faiz Usmani's family alleged that he was tortured during the interrogation.
Police denied the charge but ordered an investigation.
"He was brought for questioning by the Chembur unit of Mumbai police. He was suffering from hypertension. The allegations of torture by police are absolutely untrue," said Nisar Tamboli, a police spokesman.
Police were making incremental progress in the investigations into the three blasts Wednesday that killed 19 people and wounded 130 others.
All three bombs that exploded at three crowded places in downtown Mumbai were packed inside metallic containers and triggered by digital timing devices, said Rakesh Maria, a top investigator.
However, Maria, who heads the anti-terrorism squad in Maharashtra state, said investigators were not in a position to name any terrorist outfit as being responsible for the blasts. Mumbai is the capital of Maharashtra state.
On Sunday, police arrested a man in the western Indian state of Gujarat who was allegedly in possession of 10 crude bombs. The man was being questioned, but there were no immediate details on the bombs.
Police in at least six states were involved in the investigation focused on possible links between the blasts and terrorist groups, Maria said.
Investigators have been questioning two suspected members of the Indian Mujahideen, a banned Muslim terrorist group with links to Lashkar-e-Taiba, the Pakistan-based militant outfit that has claimed past terrorist attacks that used similar explosives.
The blasts were the deadliest terrorist attack in Mumbai since a 2008 siege in which 166 people were killed in an assault that lasted three days.
No group has claimed responsibility for Wednesday's bombings.