The Gujarat Police have formed teams to unearth a suspected illegal immigration network involving "agents" and will coordinate with the passengers of a plane that has landed in Mumbai from France, a senior official said.

Many passengers of the plane hail from Gujarat, he said.

The aircraft, an Airbus A340, carrying 276 passengers, mostly Indians, was grounded in France for four days over suspected human trafficking. It landed in Mumbai in the wee hours on Tuesday.

"The CID crime wants to take action against agents who had promised help to the victims to enter the US and other countries (illegally). We have formed four teams which will get information from the victims regarding promises made to them by these agents," Superintendent of Police, CID (Crime), Sanjay Kharat said.

He said most of the passengers on the chartered plane that returned from France were from Banaskantha, Patan, Mehsana and Anand districts in Gujarat.

"Police will coordinate with the passengers when they reach Gujarat from Mumbai to find out the agents and agencies involved and whether documents provided to them to migrate to the US and other countries were forged," he said.

The official said they will also try to find out how many people have been flown abroad this way, and who all are seeking to travel in this manner.

The CID has so far received "raw information" regarding the agents involved in the incident and will be able to find out more only after questioning the passengers concerned, he said.

Kharat said different agents involved in illegal immigration work in tandem.

"The agents working at the village and district levels are small players controlled by a kingpin who works at the international level," he added.

The Gujarat police will investigate and get a clear picture of how they operate, he said.

"Different agencies use different modus operandi based on the requirements of persons seeking to migrate like whether they require forged documents etc, and rates are fixed accordingly," the SP said, adding the victims will be questioned and police will reach the kingpin.

The chartered flight, which was operated by Romanian charter company Legend Airlines and bound for Nicaragua, landed at Vatry near Paris on Thursday for a technical stopover en route from Dubai when the French police intervened.

French authorities launched a judicial investigation into the conditions and purpose of the trip, with a unit specialising in organised crime investigating suspected human trafficking.

In Mumbai, immigration authorities enquired from some of the 276 passengers, an official said, adding no passenger was detained and they were allowed to leave the airport by 11.30 am on Tuesday.

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