TEHRAN, Jan 7: Iranian authorities put a major oil- and gas-producing area in southwest Iran on a state of "maximum alert" on Wednesday after 26 earth tremors jolted the region in less than 36 hours , state TV reported.

The measure, ordered by President Mohammad Khatami, was taken in and around the towns of Masjed Soleiman, Izeh and Baghmalek - situated around 450 kilometres southwest of Tehran in Khuzestan province.

The report said a succession of tremors, measuring between 2.7 and 4.9 on the Richter scale, had jolted the area since early Tuesday. Iran has been on a quake footing after a massive earthquake hit the southeastern city of Bam on December 26, killing up to 35,000 people.

"The president has given the order to the concerned services to be on maximum alert and we are very worried," Masjed Soleiman's prefect, Sattar Akbarzadeh, told state television.

The official also warned that in Masjed Soleiman there was a major risk of potentially explosive leaks from the vast oil and gas field underneath the city.He nevertheless called on residents to "remain calm", while revealing that overnight "people had been sleeping on the streets or in prepared areas even though there was heavy rain" and appealed for 20,000 tents.

"All administrative services in the province have been placed on maximum alert," Shapour Rostami, an official from the provincial natural disasters unit, also told state television.

"We have prepared three camps around the towns of Masjed Soleiman, Izeh and Baghmalek, and all schools have been closed," he said. "All facilities in the three towns have been mobilized, and all facilities in the province are ready to be sent there if needed."

Masjed Soleiman was last hit by a major quake in September 2002, when an earthquake measuring 5.5 on the Richter scale caused five injuries.-AFP