Mumbai, July 27 - A Mumbai couple and their associate were Monday convicted by a special court of triggering the Aug 25, 2003 twin blasts which killed 54 people and injured 244 more at Gateway of India and Zaveri Bazar here.

The three main accused -- Mohammed Hanif Sayed, 42, Fahmida Mohammed Sayed, 36, and their close aide Ashrat Shafique Ansari, 32 -- were found guilty by the Prevention of Terrorism Act (POTA) Special Judge M.R. Puranik. They will be sentenced Aug 4.

The fourth accused, Zahid Yusuf Patni, who was the chief of a Lashkar-e-Taiba (LeT) module named Gujarat Revenge Force through which he hatched the conspiracy in Dubai, had turned approver in the case.

The Sayeds' minor daughter Farheen, though involved in the twin bombings, was not charged under POTA and was discharged from the case a few years ago, said defence lawyer S. Kunjuraman.

The terror attacks on Aug 25, 2003, shook the tourist hub of Gateway of India and the congested Zaveri Bazar, the hub of the gold jewellery business in south Mumbai.

The bombings were carried out ostensibly to 'avenge' the death of Muslims killed during the 2002 Gujarat riots that broke out in the wake of the Godhra train burning on Feb 27 that year.

According to Special Public Prosecutor Ujjwal Nikam: 'This (the judgement) is a major jolt for the LeT and it is the first time in India that a family has been found guilty of carrying out terrorist operations.'

In view of the serious charges, the prosecution would seek the most stringent punishment of death for the guilty, he said.

Two other accused in the case, Rizwan Laddowala and A.