WASHINGTON, Aug 6: An Al Qaeda suspect arrested in Britain directed the surveillance of US financial institutions years ago that led this week to a heightened security alert in the United States and a worldwide crackdown on terrorist suspects , US media said on Friday.

Identified as Abu Issa al-Hindi - a Pakistani intelligence officer said his name was Abu Eisa Al Hindi and described him as "a senior Al Qaeda man" - the suspect was "intimately involved" in producing and perhaps writing the reconnaissance reports found on computer disks in Pakistan last week, unnamed senior US officials told The New York Times.

Al-Hindi's arrest on Tuesday could be important in the drive to track down Al Qaeda operatives inside the United States, the USA Today daily said, quoting top-level US government officials.

It was unclear whether Al-Hindi conducted the surveillance of the US financial institutions in 2000 and 2001 himself or through other Al Qaeda operatives, both dailies pointed out. But one law enforcement official told NYT there was evidence he did carry out surveillance on the New York Stock Exchange and the Citigroup building in New York City's Manhattan island, and at the Prudential site in Newark, New Jersey.

US officials announced Sunday that Al Qaeda had targeted the three sites in New York and New Jersey as well as the International Monetary Fund and the World Bank in Washington.

In response, authorities raised the colour-coded alert level from yellow, or "elevated," to orange, or "high," for the three US cities and boosted security around the targeted areas.

The alert level was raised after information was gathered in Pakistan from computer files belonging to an Al Qaeda suspect identified by the Pakistani press as Muhammad Naeem Noor Khan, a Pakistani computer engineer, and Ahmed Khalfan Ghailani, a Tanzanian indicted over his alleged role in the 1998 US embassy bombings in east Africa.

The breakthrough in Pakistan triggered a world wide crackdown on Al Qaeda. The arrest of Khan and Ghailani was facilitated by a Pakistani military crackdown on Al Qaeda hideouts along the border with Afghanistan which forced the extremist operatives into more vulnerable urban areas, The Washington Post said on Friday. -AFP