MUMBAI -- With bullets lodged in both arms, suspected terrorist Mohammed Ajmal Kasab could no longer hold the AK-47 rifle police say he used to kill dozens of people during his three-hour rampage through Mumbai. So he and a partner fled the violent upheaval their fellow terrorists were still causing.

A police chase led to the death of his partner and Mr. Kasab's capture, giving authorities what they call a wealth of insights into the plot -- and into how they say a disaffected young man joined an Islamic militant group and carried out a terror mission that left 171 people dead.

The gunman identified by police as Mohammed Ajmal Kasab walks through Mumbai's main train station, where more than 40 people were killed. Associated Press

When he was caught in a stolen car past midnight, near Chowpatty Beach just outside of downtown, Mr. Kasab told police he was searching for a solitary place to remove the bullets that hit him. He and his partner had hoped to continue their rampage, according to Deven Bharti, a commissioner of Mumbai police's crime branch.

From repeated interrogations, a portrait of Mr. Kasab is emerging, Mumbai police say. He has told investigators he was from a poor family and was easily recruited two years ago by Lashkar-e-Taiba, the militant outfit that grew out of Pakistan's push for independence in India's contested region of Kashmir. In Lashkar's fold, police say, Mr. Kasab thrived. He told investigators he passed through a succession of militant training camps with a sense of purpose for the first time in his life. Indian authorities said senior Lashkar-e-Taiba leaders planned last week's attacks.

"He was led to believe that he was doing something holy," said Rakesh Maria, joint commissioner of Mumbai police.

A senior Mumbai police official said that Mr. Kasab described receiving training from former Pakistani military personnel. Pakistan denies any involvement in the attacks.

Mr. Kasab, whom police said is in his early 20s, has said he was born outside Faridkot village in the Punjabi section of Pakistan. A dusty enclave of mud and stone buildings, inhabited mostly by semiliterate farmers and laborers working in nearby cities, Faridkot is a fertile area for militant recruits.

How much truth there is to his account, however, remains in dispute. A senior Pakistani security official said they have found no evidence Mr. Kasab came from the village. Pakistan's president, Asif Ali Zardari, said Wednesday in an interview on CNN that he doubted the sole suspect being held in the attacks by India is a Pakistani citizen, as Indian police claim.

Indian police officials counter that much of the information Mr. Kasab has provided so far has proved accurate. He disclosed the location of a fishing trawler that the terrorists used to enter Mumbai's coastal waters. On the boat, Mr. Kasab told investigators, they would find the ship's captain dead, a satellite phone and a global-positioning device. They did.

Police officials said they are still trying to verify other details, such as the identities of the nine other assailants who were slain. Among themselves, they used aliases to disguise identities.

Mr. Kasab told police of a hardscrabble life that led him to Lashkar, they say. His father supported him and four siblings by selling snacks from a cart. He dropped out of school in fourth grade to work but eventually left home. In 2005, he headed to Lahore, one of Pakistan's biggest cities, to seek work, but eventually hooked up with Lashkar recruiters instead, police said.

After recruiting him, Lashkar trained Mr. Kasab in a variety of camps around Pakistan, according to Messrs Maria and Bharti. He was trained to fire weapons, detonate explosives and take hostages. Mr. Kasab also attended a camp dedicated to marine combat -- a precursor to the group's hijacking of the fishing trawler that brought them to Mumbai, he told police. He was indoctrinated in the principles of militant Islam.

After 18 months, a sinewy militant emerged, according to Mr. Bharti. "He was physically tough, mentally tough," the senior police official said after reviewing closed-circuit-television footage of Mr. Kasab's killing spree in Mumbai's main train station. "Look how confident he is. How well-trained he must have been."

At the station, Mr. Kasab and his partner threw a hand grenade into a crowd, and then opened fire. Moving along separate paths toward the station's main entrance, he and his partner fired as they walked. By the time they left, more than 40 people, including three police officers, were dead.

Cameras caught a young man in a black T-shirt and khaki cargo pants strutting through the station carrying a rifle and blue bag of spare ammunition. The gunmen also turned up at nearby Cama Hospital, shooting two unarmed guards and trading fire with police on the top floor before running outside and hiding behind a bush. Officers returned fire, hitting Mr. Kasab in both arms.

Mr. Bharti said Mr. Kasab and his partner had no intention of returning to Pakistan. "It was a suicide mission," he said. After being admitted to a hospital, he began talking to police. Police expect more information, but they declined to say how they are extracting it and deny any torture. "We have our techniques," said Mr. Bharti. "He will sing like a canary."

—Zahid Hussain in Islamabad contributed to this article.

Write to Peter Wonacott at and Geeta Anand at