Q+A - Who could be behind the Mumbai attacks and why?

MUMBAI (Reuters) - Militants armed with automatic weapons and grenades attacked luxury hotels, hospitals and a famous tourist cafe in India's commercial capital Mumbai late Wednesday, killing at least 101 people.

* WHO IS BEHIND THE ATTACKS?

The attacks were claimed by a previously unknown group calling itself the Deccan Mujahideen in an e-mail to news organizations. Deccan is an area of southern India.

But it is not clear if the claim is genuine, and analysts say the bombings are almost certainly the work of a different group.

The most likely perpetrators, they say, are either the Indian Mujahideen or Lashkar-e-Taiba.

* WHO ARE LASHKAR-E-TAIBA?

Lashkar-e-Taiba is one of the largest Islamic militant groups in South Asia, based in Pakistan and fighting Indian rule in Kashmir. Security analysts say it is a well-funded and highly organised group that sympathises with al Qaeda.

Lashkar-e-Taiba denied being behind the Mumbai attacks and said it condemned them.

The group was blamed for bomb attacks on markets in New Delhi that killed more than 60 people in 2005, as well as an assault on India's parliament in 2001 that brought India and Pakistan to the brink of a fourth war.