At least 180 people are dead and more than 625 wounded after eight near-simultaneous bomb blasts rocked Mumbai's commuter rail network during the evening rush hour on Tuesday.

Authorities have described the explosions as a well-coordinated terrorist attack.

The series of blasts struck Mumbai's western suburbs in quick succession, ripping apart train carriages and forcing some passengers to jump from trains -- a tactic commonly employed by Kashmiri militants.

The first blast hit a train at a railway station in the suburb of Bandra at about 6:20 and was followed by attacks at Khar, Jogeshwari, Mahim, Mira Road, Matunga and finally two blasts at Borivili ending at 6:35 p.m local time, the Star News Channel reported.

"Most of these blasts took the commercial capital by surprise, because that's the time when the peak traffic is there and people are returning home from offices," India Times editor Girish Chadha told CTV Newsnet.

India's Home Minister Shivraj Patil told reporters that authorities had some information that an attack was imminent "but place and time was not known."

There was no immediate claim of responsibility, but suspicion quickly turned to Muslim militants fighting New Delhi's rule in disputed Kashmir. Pakistan's government quickly denounced the blasts.

Chaos

Chaos gripped the railway network in India's financial capital as authorities struggled to aid the wounded and determine the number of casualties.

Indian television news channels aired images of dazed survivors being helped to waiting vehicles while bloodied victims remained sprawled on train tracks amid luggage and debris.

"It took about 20 to 25 minutes for the emergency workers to come, because it wasn't just at one railway station," witness Jemcy Jacob told Newsnet.

Western Railway spokesman Pranay Prabhakar said all trains had been suspended and urged the public to keep their distance from the city's railway stations.

The Press Trust of India (PTI) news agency reported that local phone lines were jammed as anxious people tried to reach their loved ones.

All of India's major cities were placed on high alert following the blasts and Indian Prime Minister Manmohan Singh called top officials to an emergency meeting to discuss the violence.

"It is a sad day," Home Secretary V. K. Duggal told reporters. "Security has been definitely put on high alert."

In Canada, Foreign Affairs Minister Peter MacKay described the bombings as "a deplorable act of violence against innocent civilians."

In a statement, MacKay said, "Canada stands with India in condemning these acts of terror perpetrated by those who value human life less than their own extreme beliefs."

Tuesday's blasts came hours after a series of grenade attacks by Islamic extremists killed eight people and wounded two dozen more in Indian Kashmir's main city of Srinagar.

Kashmir has been split between Hindu-dominated India and Muslim-dominated Pakistan after the two countries gained independence from Britain in 1947, but both claim it in full.

Mumbai, a metropolis of about 17 million, has been rocked by a series of bombings over the past ten years.

Authorities blame the city's underworld criminal gangs for being behind a string of bomb blasts in 1993 that killed more than 250 people and wounded more than 1,000 people.

U.S. officials in Washington told The Associated Press that it was too early to know for certain what group was behind the attacks.

However, one, speaking on condition of anonymity, said the modus operandi of Tuesday's attacks fit two Islamist extremist groups: Lashkar-e-Tayyaba, or Army of the Righteous, and Jaish-e-Mohammad, or Army of Mohammed.

Both have been designated by the U.S. government as terrorist organizations. They are considered affiliates of al Qaeda.

With a report from CTV's Tom Kennedy and files from The Associated Press