This was the second major blast in the last decade and came a day after the city observed the 10th anniversary of 1993 serial blasts.

On March 12, 1993, 13 explosions shattered the city of Mumbai, killing 257 people and injuring 713 besides damaging property worth 300 million rupees (US$6.30 million).

Thursday's blast occurred on two carriages, a general and a first class Ladies, of a Karjat-bound local train, while it was pulling into the platform at Mulund.

The police said that the explosions, which blew off the roof of the ladies carriage, were caused by a bomb planted between the two carriages.

At least 21 of those injured were said to be in a serious condition. They were all rushed to local hospitals.

No one has claimed responsibility for the blasts so far. However, police said the explosive device used was similar to the one used on a bus at Ghatkopar, in the same area, on Dec. 3, 2002.

Police said though the bomb was planted on the right side of the train, the blasts were so powerful that several people on the platform (on the left of the train) were also injured.

"It is a mess out there. We have rushed the fire department, wireless vans and officers, but commuters rushed many of the injured to various hospitals in and around Mulund on their own," a police official said.

A witness said that most of the victims were injured above the waist.

At the time of the explosion, Mulund station was crowded with office workers. Panic swept through the station and traffic on the route was stopped. Police cordoned off the area, trying to keep hundreds of onlookers from breaking through the barricades.

Maharashtra State Home Minister Kripashankar Singh said that the authorities had expected an attack, considering it was the 10th anniversary of the March 12 blasts in Mumbai.

He said, "Police was on a high alert. Despite that the tragedy occurred, there is also a possibility of some mischief. Nothing can be said for now about who was behind the blast."

However, police said they suspected a banned Islamic students group bombed the train.

"It could be linked to the Students' Islamic Movement of India (SIMI)," Joint Police Commissioner Ahmad Javed said in Mumbai.

The accusation came a day after New Delhi stepped up its crackdown on SIMI, arresting some of its leaders.

"The pattern of the blast is very similar to the one which happened in the passenger bus," Javed said, referring to a blast in Mumbai on Dec. 2, 2002, killing two people and injuring 27 others, which police blamed on SIMI.

But Javed did not rule out the possibility, however, that another "terrorist group" could be behind the train bombing.

Meanwhile, police sounded a red alert in Mumbai late Thursday night and organized combing operations in sensitive areas in the wake of the powerful blast in the local train.

Special police teams have been formed and sent to important railway stations to maintain night long vigil.

Combing operations were organized at strategic locations, police said, adding security has been tightened all over the city, particularly at sensitive places such as airport.

In New Delhi, police and other security agencies were put on alert since Thursday night following the blast in the Mumbai train.

"Although security is already intense in the national capital due to the looming terrorist threat, forces were alerted in the wake of developments in Mumbai," a top police official said.

Personnel manning security of vital installations have been particularly asked to be extra vigilant, he said.

The official said any subversive activity anywhere in the country usually has a bearing on Delhi being the national capital and the target of terrorists.

Recently, India Gate, a prominent tourist destination, was sealed after intelligence agencies warned of terrorist plans to attack there.

A Jaish-e-Mohammed terrorist, who allegedly was planning the attack, was killed in a police encounter in Noida, on the outskirts of the capital, on Wednesday.

(Xinhua News Agency March 14, 2003)