Pakistani Group Behind Mumbai Attacks?

According to the Times of India, security forces have captured several Pakistani men:

Police and central security personnel have arrested at least three Pakistanis including Ajmal Amir Kamal, a resident of Faridkot near Multan in Pakistan's Punjab province. All the three belong to the suicide squad of Lashkar-e-Taiba.

Update: The Times of India now writes that '[i]n all, nine terrorists were killed while one was captured alive in "Operation Tornado" executed by the NSG alongwith the army and naval commandos and Maharashtra police." The AP reports that the captured man's name is Mohammad Ajmal Qasam. The police allege that he is a Pakistan national and affiliated with groups in that country.

Lashkar-e-Taibab is based in Pakistan and aims to end Indian rule in Kashmir. However, there is no confirmation as yet if the Pakistan group is responsible for the Mumbai carnage. There remains a significant amount of uncertainty--and rumormongering--about the attackers. Pakistan has questioned reports of its citizens' involvement, as "India [has] in the past blamed Pakistan for terrorist attacks but subsequent probes [have] shown they were carried out by 'internal groups.'" Further, according to a Times article published late Thursday, Pakistan has released an official denial:

"Pakistan played no role in the Mumbai attacks," [Pakistan's] Defence Minister Chaudhry Ahmed Mukhtar said as investigators in Maharashtra suggested that Pakistan-based Lashkar-e-Toiba could be involved in the unprecedented strike.

Aside: Again, I ask: why didn’t these men kill themselves—especially if they’re members of a suicide squad? Was there a niggle about the surety of heavenly reward?