Sources in Delhi Police said Jundal's role was being examined in the larger conspiracy behind the Jama Masjid attack in 2010, a fortnight ahead of the Commonwealth Games to "avenge" the Batla House encounter in which suspected Indian Mujahideen operatives were killed.
Sources said they are likely to seek extension of police remand when Jundal will be produced before a court when his custody ends on July five.
Soon after the arrest of Jundal became public, a Mumbai court yesterday issued a production warrant against him.
Equipped with the production warrant, a team of Mumbai Police will now file an application in a Delhi court seeking the custody of Jundal and bring him to Mumbai to stand trial in 26/11 case.
However, if Delhi Police manages to get extension of Jundal's custody, then Mumbai Police will have to wait for some more time till he is sent to judicial custody.
Jundal, who is currently in a 15-day police custody, was arrested on June 21 after a 43-month international hunt. He was detained in Saudi Arabia and sent here five days ago.
30-year-old Zabiuddin with another alias Riyasat Ali is an Indian national who is believed to have issued directions from a 'control room' in Pakistan to 10 terrorists who went on a rampage in Mumbai in November, 2008 killing 166 persons.