Four people associated with the banned Student Islamic Movement of India (SIMI) were arrested in connection with the city serial blasts in which 55 people lost their lives, police on Thursday said.

Those arrested are Abbas Sameja, Naved Kadri, Aiyaz Saiyeed, Javed Ahmed, police said, adding that apart from Abbas who is from Kutch, the other three belong to Ahmedabad.

"We have arrested four SIMI men who were involved in the city serial blasts," Joint Commissioner of Police of Crime Branch Ashish Bhatia, who is investigating the case, said.

Abbas, who works as instructor in a private health club, had sold a house, which was purchased in Bhuj by SIMI in 2001, and provided the money to partly finance the city serial blasts, police said.

He was involved with SIMI from 2001 and had attended the Halol terror training camp organised by the banned outfit in January 2008 under a fake name.

Naved, another active SIMI worker, was present during the planning meetings for the serial blasts in Juhapura.

"Naved had played a key role in execution and planning of the serial blasts," police said.

He was very close to blasts mastermind Mufti Abu Bashir. Aiyaz, another arrested, is one of the planters of the bombs in different areas of the city.

Police said he had planted the bombs mounted on cycles in different parts of the city including Naroda Gam area on the instruction of one Qayamuddin, who is absconding.