The indictment of four alleged Pakistani masterminds of the 2008 Mumbai terror attacks, including two men linked to Islamabad's security forces, is seen by US media as a "major development" in the case.
The indictment filed Monday never mentions the Pakistani security forces or their alleged role in the attacks, New York based investigative journalism group, noted ProPublica in an article in the Washington Post Tuesday.
"But it represents a major development in a secretive and diplomatically sensitive prosecution set for trial next month, because Pakistan is considered a close US ally in the fight against terrorism," it said
Prosecutors charged the four Pakistanis with playing lead roles in the attacks, suspected to have been organized by the Pakistan based Lashkar-i-Taiba (LeT) terrorist group.
The indictment identifies a man known only as Major Iqbal as one of the masterminds, who allegedly directed and funded months of reconnaissance in Mumbai by Pakistani American David Coleman Headley, who has pleaded guilty.
The indictment describes Iqbal as "a resident of Pakistan who participated in planning and funding attacks by Lashkar."
But ProPublica noted US and Indian anti-terrorism officials and Indian court documents allege that Iqbal was a serving officer in Pakistan's Inter-Services Intelligence (ISI) agency.
He allegedly acted as Headley's main handler, one of at least three ISI officers suspected of involvement in recruiting, training and directing Headley in terrorist activities, according to US and Indian investigators and Indian court documents, it said.
The other significant figure indicted on Monday is a longtime Lashkar chief named Sajid Mir, who also is accused of serving as Headley's handler, ProPublica said.
Mir, who remains at large, according to investigators, was a key plotter of the Mumbai attacks. His voice was caught on tape directing the slaughter by telephone from a safe house in Pakistan, according to officials and documents.
Some Western anti-terrorism officials think Mir spent time in the Pakistani security forces, while others say he was close to the ISI but was not a serving officer, ProPublica said.
Also charged Monday was Abu Qahafa, who is accused of overseeing the training of the attack team. Suspect Mazhar Iqbal, alias Abu al-Qama, is the only one of the four known to be in custody in Pakistan.
The fifth accused, Chicago-based Pakistani-Canadian Tahawwur Rana, who allegedly assisted Headley's reconnaissance efforts in India and Denmark, is set to go on trial in Chicago on May 16.