NEW YORK: Identified only by four-digit numbers to conceal their identities, five British Security Service officers testified Tuesday at the US trial of a Pakistani terrorism suspect charged with plotting to bomb a shopping mall in Manchester, England.

The MI5 agents described weeks of surveillance they conducted on Abid Naseer in 2009, including his movements to and from an Islamic center, a cybercafe and elsewhere, going grocery shopping and riding public buses.

US District Judge Raymond Dearie previously approved a request to disguise the agents in wigs and makeup after prosecutors said a “disclosure of their identities would pose a significant risk to their safety.”

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The agents appeared to be wearing makeup and their faces were left blank by courtroom sketch artists. Naseer was the leader of the Manchester cell of a broader al Qaeda conspiracy to attack civilians in the UK, New York and Denmark, prosecutors have said.

He was monitored during a case dubbed by MI5 as “Operation Pathway,” and the agents said he was given the code name “Small Panel. “

Other suspects were given code names such as “Happy Skater,” “Glass Pendant” and “Undercurrent,” the officers testified.

Naseer, 28, is defending himself in federal court in Brooklyn and has pleaded not guilty.

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Asked during cross-examination if his movements in and around the Manchester area in March and April 2009 appeared suspicious or caused any alarm, an agent said no.

But prosecutors say Naseer used the names of women as references to bombs in emails.

And none of the MI5 agents or other law enforcement officers who monitored him in 2009 testified they'd ever seen him with a woman.

Naseer has claimed he wrote about women only because he was pursuing a bride.

The Pakistani man was extradited in 2013 to New York City. Prosecutors claim emails shows that Naseer and two men convicted of planning to bomb New York's subways, Najibullah Zazi and Zarein Ahmedzay, were all under the direction of the same al Qaeda handler.

They also say a now-declassified document recovered during the raid that killed Osama bin Laden names Naseer and the Manchester and New York plots.