New Delhi: In an unprecedented move, a specially arranged non-scheduled flight carrying 311 Indians, escorted by nearly 60 security escorts, will reach Delhi airport early on Friday. Immigration sources have confirmed that these Indians had illegally reached Mexico over the last few months with the help international agents who had allegedly promised them entry into the US through illegal means.

"Majorly these passengers travelled from India through two private airlines to Mexico and were facilitated by travel agents, who charged Rs 25-30 lakhs per person," a senior immigration official said, requesting to withhold identity.

"The cost includes stay, air fare, meals etc. Agents took around a week to a month's time to arrange entry into the US," the official added.

Sources have also said that the flight Boeing 747-400 is reaching India via Madrid in Spain and all Indians have been given Emergency Certificates- a one-way travel document that allows an Indian citizen to enter India in an emergency.

Such papers are issued to individuals, who lose, damage or have no valid passports.

"The National Immigration Institute (of Mexico) said in a statement late Wednesday that it had flown the 310 men and one woman to New Delhi from Toluca," The Washington Post reported, quoting the Associated Press.

"Mexico has stepped up its immigration enforcement in recent months under pressure from the United States. The government has deployed thousands of National Guard agents along the major migration routes," the publication's report further stated.

"The process of repatriation will take not less than 3-4 hours as government agencies will question them regarding their travel. A legal case may also be registered in the matter and role of insiders will be probed," another senior immigration official told ANI.

Majority of repatriated Indians are from Punjab who had traveled to Mexico at frequent intervals.