The roads outside Delhi airport's Terminal 3 were blocked, the police said.
A bag with suspected RDX caused a major security scare at the Delhi airport in the early hours of Friday, leading to blockades and affecting the movement of passengers for a few hours, officials said. Security at the airport has been tightened, say the police.
The black bag was first detected around 1 am by a personnel of the CISF or Central Industrial Security Force in the arrival area of the airport's sprawling Terminal-3. It has now been kept in a cooling pit.
Preliminary inputs suggest the contents of the bag may include RDX. It was checked by an explosive detector and a sniffer dog. The exact nature of the explosive is being ascertained, Press Trust of India quotes sources as saying.
The sources said the explosive would be under observation for 24 hours before anything certain could be concluded about it.
According to PTI, the bag may have contained an explosive or an improvised explosive device (IED).
The Delhi Police said it was alerted to the mysterious abandoned bag around 1 am.
"The bag was removed with the help of CISF and shifted to another place. It has not been opened yet. It seems like there are some electric wire inside it. We have increased the security of the airport premises," said Sanjay Bhatia, Deputy Commissioner of Police (Airport).
The incident caused panic at the airport as passengers were not allowed to exit the terminal for some time, sources at some airlines said.
Officials said the CISF and Delhi Police carried out a complete anti-sabotage check of the Indira Gandhi International Airport and only after that, around 4 am, passenger movement was allowed.
The roads outside the high-security complex were also blocked.
Delhi's airport has three terminals; domestic as well as international flights operate from Terminal-3, the newest extension of the airport.
(With inputs from PTI)