Amsterdam/New Delhi, Aug 24 (IANS) Twelve persons detained in Amsterdam for questioning after a security alert on a Northwest Airlines flight were Mumbai-born even as the flight took off a day after it was grounded at Schiphol airport following a security alert that it had possible terrorists on board.

"We have got the list of 12 people. They all were born in Mumbai. Nobody has been arrested as per the latest information but detentions are there," Minister of State for External Affairs Anand Sharma told reporters here Thursday.

The Indian embassy in Amsterdam has been granted consular access to the 12 detained people, who all had addresses in Mumbai, the minister said.

"We have to ascertain and get the details. They are all from Mumbai and they all have Mumbai addresses," Sharma said.

"We are in constant touch with the Dutch authorities on this issue. The nationality of the detained people is not yet clear," an official at the Indian embassy in The Hague told IANS over the phone.

"There are strict privacy laws in the Netherlands. That's why the Dutch authorities have yet to give us adequate information on the detained people," he added.

However, neither the Dutch justice ministry nor the border police, who detained the passengers, would comment on the circumstances that led the flight to return to Schiphol shortly after take-off before noon Wednesday.

Two Dutch F-16 fighters Wednesday escorted a Mumbai-bound flight of Northwest Airlines back to Schiphol Airport carrying 149 passengers, an hour after the take off after the pilot expressed some "security concerns."

"The captain of the aircraft had some security concerns. We don't have specific information as yet. But some passengers were taken out for questioning," Mirjam Snoerwang, spokesperson for Schiphol Airport, told IANS.

Even as the Dutch authorities question the 12 detained persons, the flight took off for Mumbai Thursday morning.

The flight took off at 10:53 a.m., an official at the Schiphol Airport said.

Meanwhile, the decision by the captain of the flight NW0042 to return to Schiphol and subsequent events have sparked feverish speculation in the Dutch media.

The daily Telegraaf reported on the basis of comments from one of the passengers that two armed US air marshals had taken control of the DC-10 following suspicious behaviour by a group of men.

Other reports said the crew reacted after a mobile telephone rang and the men cheered in response.