Al Qaeda has increased the pace of its recruitment and is trying to develop explosives that are harder to detect by the security equipment used in airports, Pakistani daily Dawn said quoting counter-terrorism experts and intelligence reports.
These explosives can be moulded into shoes or luggage, the report quoted experts saying.
"It is unlikely," they said, "that a terrorist team would follow the example of the September 11 hijackers spending months in the US before a new attack."
Pakistani intelligence officials, quoted by The Friday Times, said some Al Qaeda cells had regrouped and could mount terrorist attacks on the first anniversary (June 14) of the suicide bombing on the US consulate building in Karachi.
Among the recent major arrest of Al Qaeda activists included that of Tawfiq bin al-Attash, who was the mastermind of the 2000 bombing of American warship USS Cole.
The raids in which al-Attash was caught also led to the capture of truckloads of explosives, which led the agencies in Pakistan to express surprise as to how could such a large amount of bomb-making materials be smuggled into the country.
The intelligence officials, who interrogated al-Attash said, "We believe that he managed to establish a network of unspecified number of suicide attackers before getting arrested. We still don't have any leads to those potential attackers. So, his arrest has not eradicated the threat."
The Dawn also pointed towards a taped message in which the voice 'widely agreed to be that of Osama bin Laden' described Morocco, Saudi Arabia, as well as Pakistan, Nigeria, Jordan and Yemen as targets for 'martyrdom operations'.