Fresh gunfire and explosions were heard late Thursday in Mumbai as police battled terrorists at three sites about 24 hours after the first wave of violence hit the city.
Two of the hostages freed after police stormed the Oberoi Hotel in Mumbai.
Indian Prime Minister Manmohan Singh suggested the group behind the terrorist attacks, which killed 125 people, was based outside the country.
CNN reporters said regular gun fire and blasts could be heard at the Oberoi and Taj Mahal hotels and a Jewish center in the city.
Police had some success with 10 hostages reportedly freed from the Oberoi despite a major fire.
Shortly after authorities said the siege had ended at the Taj Mahal hotel, two explosions were heard, similar to the six blasts heard earlier. Video Watch more on hostages being released »
It was not immediately clear what caused any of the explosions. Witnesses said continuous gunfire could be heard at the hotel.
A fire from earlier billowed smoke through one of the hotel's windows, as firefighters poured water over the plumes.
A few blocks away, at the Hotel Oberoi, a major fire raged Thursday night through one floor there, CNN's sister network in India, CNN-IBN said. Video Watch flames pouring from the Oberoi »
The network reported 30 people were trapped, and said gunshots could be heard. Later, an explosion was heard from the hotel's rear side.
At least three or four terrorists are still holding hostages in both the Taj Mahal and Oberoi hotels, British officials told CNN on Thursday. Are you there? Send your photos, stories
Meanwhile, Singh suggested the group behind the attacks probably had "external linkages."
"It is evident that the group which carried out these attacks, based outside the country, had come with single-minded determination to create havoc in the financial capital of the country," he said. The death toll from the series of coordinated attacks was at 125, including at least six foreigners, by Thursday evening authorities said. An Italian and Briton were among the confirmed dead.
Another 327 people were wounded in the attacks, including seven British, three American and two Australian citizens. Video Watch more on who is responsible »
In addition, at least nine gunmen were killed in fighting with police. CNN's sister network in India, CNN-IBN, quoted police sources as saying they believed there were around 26 gunmen, most of them young.
Also among the dead was Hemant Karkare, the chief of the Mumbai police's anti-terror squad, and 14 police officers.
Indian officials have told Canada that they believe six Canadians are being held hostage in the two hotels, according to a senior aide to Prime Minister Stephen Harper. The Canadian government has no information of its own to confirm the number or to ascertain if they are among the dead or injured, being held captive or just stuck in the hotels.
Authorities found 8 kilograms (17 pounds) of RDX, one of the most powerful kinds of military explosives, at a restaurant near the Taj, indicating that the attackers may have been planning more violence.
Gunmen also remained holed up in a building called Chabad House, where several Jewish families live. Rabbi Gabriel Holtzberg, the city's envoy for the community, was being held inside with his wife, a member of the Hasidic Jewish movement said. The couple's 18-month-old baby was released unharmed.
Read more on group claiming responsibility
Two women and an infant were seen escaping from the building but three to four residents remained captive inside, an Indian official said.
Police said gunmen fired indiscriminately from the building. Stray bullets killed a couple in their home and a 16-year-old boy who stepped outside, police said.Police surrounded the building and exchanged gunfire in which one of the gunmen reportedly was shot,
A standoff at a fourth location -- the Cama Hospital for women and infants -- appeared to have been resolved by Thursday morning, CNN-IBN reported. It was not immediately known whether gunmen at the hospital fled or were killed.
Authorities locked down Mumbai and asked residents to stay inside. The stock market in the city -- India's financial hub -- was closed, as were schools and colleges. The city is also home to Bollywood, the Hindi-language film industry.
Government officials said the attacks caught them completely unaware.
Police say the attackers came by boats to the waterfront near the Gateway of India monument.
IBN reported late Thursday a body being found on a fishing trawler carrying high tech satellite gear and GPS equipment.
Of the nine suspects arrested in connection with the attacks, seven are fishermen. Police also found a boat loaded with explosives near the Taj, which is located on the waterfront.
"Those men were wearing jackets and they carried big big bags," one fisherman told CNN-IBN.
Said another: "We asked, 'Where are you coming from?' They said, 'Go do your work.'"
The gunmen then hijacked cars -- including a police van -- and broke up into at least three groups to carry out the attacks, police said.
One group headed toward the Cafe Leopold, a popular hangout for Western tourists, firing indiscriminately at passers-by on the street. They then opened fire and lobbed grenades at the Chhatrapati Shivaji Terminus railway station, a Victorian building.
As police rushed to the scene of the attacks, gunmen attacked the Cama Hospital. Two other groups attacked the Oberoi and Taj hotels. Video Watch more on Mumbai's importance »
The Indian navy, stepping up patrols on the country's western coast after the attacks, boarded a cargo vessel Thursday afternoon, officials said. They and the Indian coast guard were also searching for a small boat. The operations were being conducted in the Arabian Sea.
Several Indian news outlets reported receiving e-mails from a group calling itself the Deccan Mujahideen, claiming responsibility for the attacks. CNN was not able to verify the reports.
Reaction from the United Nations, United States and United Kingdom was swift as world leaders joined in condemning the attacks. Read more on the international reaction
India has suffered a number of attacks in recent years, including a string of bombs that ripped through packed Mumbai commuter trains and platforms during rush hour in July 2006. About 209 people were killed in that attack.
Last July, a series of synchronized bomb blasts in the western Indian city of Ahmedabad left 49 dead and more than 100 wounded, police said.
Wouldn't surprise me if AQ funded this. Conspiracy theory, Hugo?
