MUMBAI, Nov. 28  -- Explosions rocked a Jewish center in Mumbai Friday as commandos took positions on its roof for a final assault to end two days of terrorists' carnage.

The center, called Nariman House or Chabad House at Nariman Point, is a favorite of Israeli tourists, who along with Britons and Americans appeared to have been the main targets of the rampaging gunmen who began their killing spree Wednesday night in the sprawling metropolis of nearly 20 million.

CNN said prior to the commando operation at the Chabad House, grenades were lobbed out from inside, targeting anyone approaching the building.

The BBC reported the troops on the ground there first dropped smoke bombs to create confusion as other commandos came down a rope to the roof top from helicopters.

The Chabad House, along with the city's two luxury hotels, the Taj and Oberoi-Trident, all located in plush areas near the Arabian Sea, remained the last holdouts of the terrorists, who killed about 125 people, including six foreigners, and injured more than 300. Many of their hostages had been freed at the hotels but it was not clear how many gunmen and hostages were at the Jewish facility, the Press Trust of India reported.

"The operation to clean up the Nariman House is still going on," Director General of National Security Guard J. K. Dutt told reporters.

Local television reports quoted authorities at Hotel Taj as saying operations at the massive century-old, 800-room landmark facility were largely over after a long night of rescuing hostages, fighting fires and battling gunmen holed up there.

Some reports said one injured terrorist also was in the Taj.

The situation at Oberoi-Trident was unclear as reporters at the scene said there was a lull Friday morning after explosions and gun fire all night long. At least two terrorists were believed to be in the hotel. There was also a huge fire earlier at the hotel.

The Press Trust of India quoted Indian Cabinet Minister Kapil Sibal as telling a local television the terrorists had meticulously planned the attack for months, conducting prior reconnaissance and even setting up "control rooms" at both hotels.

Some reports said the terrorists, some of them allegedly from neighboring Pakistan, entered Mumbai from sea.

"The terrorists were dropped by a mother ship and traveled in rubber boats which they docked (at Mumbai)," Sibal was quoted as saying.

Indian Prime Minister Manmohan Singh also said the attackers were based "outside the country" and that India would not tolerate "neighbors" who provide a haven to militants targeting it, the BBC reported. (UPI)