The Anti-Terrorism Squad on Friday said one of those arrested on Thursday for suspected links with the Lashkar-e-Tayiba could well be the fundraiser of the terrorist outfit in Mumbai.

Faizal Sheikh, who was arrested on Thursday night along with his brother Muzammil could also be crucial for cracking the case, ATS sources said.

Faizal allegedly used the hawala mode to acquire funds from Pakistan and the Middle east, sources said.

The ATS will seek the help of Central agencies to probe the hawala racket that helped Faizal transfer funds for the illegal activities. some arrests in this connection are also likely, ATS sources said.

Mumbai Crime Branch officials who picked up Faizal, a resident of Mira Road in nearby Thane district and his Bangalore-based software programmer brother Muzammil, said that Faizal and Dr Tanvir Ansari -- an LeT suspect who was arrested last week -- were motivators of the Pakistan-occupied Kashmir-based terrorist outfit and were active in Mumbai.

It was Faizal who motivated Ansari to undergo training at LeT camps in Pakistan and PoK and arranged the visit with the help of his brother Muzammil, sources said.

Subsequently, Ansari also started motivating people to join LeT training, some of them being the arrested LeT suspects including Jamir Sheikh of Mumbai and Sohail Sheikh of Pune, they said.

"Given the level of access Faizal had in the LeT hierarchy, it is possible that he was aware of LeT activities in Mumbai and around, including the plan of the untraced LeT module to execute serial bomb blasts on Mumbai suburban trains," ATS sources said.

They added that some hawala operators from Mumbai and Gujarat are likely to be questioned to ascertain if money was sent into India by suspected LeT operatives or sympathizers from abroad.

ATS sources, while admitting that they are nowhere close to nab the real perpetrators of the serial blasts, said their hopes now rest on the interrogation of Faizal, Muzammil and Tanvir Ansari, with the three most likely to have knowledge of what other LeT modules were planning in Mumbai, if not aware of the entire blasts plan.

Nearly 200 persons were killed and over 700 injured in the seven serial train blasts that took place inside first class compartments of suburban trains of Western Railway on July 11.

Eight suspected LeT members have been arrested so far in the case by a joint team of ATS and Mumbai Crime Branch.