A warning has been issued to national airline, Malaysia Airlines (MAS), for failing to observe procedures requiring passengers on its international flight to go through immigration checks on arrival in the country.

Deputy Home Minister Datuk Nur Jazlan Mohamed said the incident happened a few days ago when a MAS flight, MH741, from Yangon, Myanmar to Kuala Lumpur, with 135 passengers on board, was detoured to the Langkawi International Airport due to bad weather.

He said he was informed by the Immigration authority today that only 32 of the passengers, including Malaysians, went for the Immigration check after arriving at the Langkawi International Airport.

"We understand the aircraft had to detour to Langkawi, but when in Langkawi, procedures required passengers on international flight to be processed, like stamping of their passport, but this was not observed.

"Subsequently, the aircraft flew to the Kuala Lumpur International Airport on a domestic flight, and from there, the passengers entered the country as domestic passengers," he told reporters after opening the ASEAN and Coordinated Mekong Ministerial Initiative against Trafficking (COMMIT) Workshop: Identifying Human Trafficking Victims and Relevant Types of Exploitation here today.

Nur Jazlan, however, could not furnish details on the incident, but said it was the responsibility of the airline concerned to ensure passengers on its international flight went through Immigration procedures on arrival.

He said he had a meeting with Malaysia Airports Holdings Bhd (MAHB) yesterday on problems of passengers entering the country illegally through Malaysian airports.

He said it was the responsibility of all quarters to prevent illegal entry of foreigners into the country.

"Airline companies should also play their role by ensuring passengers on their international flight go through the Immigration check, even if there are technical problems and others," he added.