Malaysian immigration department has detained more than 30,000 undocumented migrants, including an estimated 7,000 Bangladeshis, since January this year.

Datuk Seri Mustafar Ali, director general of the department, said 30,000 illegal migrants were detained until yesterday, but he did not mention the nationalities of the migrants, who mostly come from Indonesia, Bangladesh, Nepal, India, Philippines, Cambodia and Myanmar.

Mustafar had earlier told the media that 5,959 Bangladeshis were detained between January 1 and August 29 this year. A number of Bangladeshi migrants told The Daily Star over the phone that those detained since August 30 include another 1,000 Bangladeshis.

Following a raid in Kota Kinabalu, Sabah, Mustafar Ali yesterday said over 1,000 employers were also detained during the period for employing or harbouring the undocumented migrants, reported Bernama, the state news agency of Malaysia.

"The detentions are the result of more than 10,000 operations carried out nationwide with over 100,000 foreigners examined," he told reporters.

"We gave illegal immigrants the opportunity to surrender themselves voluntarily through the 3-plus-1 programme which ended on August 30.

"In addition, we implemented the Rehiring Programme which was terminated on June 30. However, we still find many who do not adhere to the set procedures."

Mustafar said despite a large number of operations carried out, there were still many illegal immigrants located throughout the country.

"Although we have introduced several programmes, many still refuse to surrender, including employers. After the Rehiring Programme, we implemented Ops Mega 3.0 and of the hundreds of operations that we have conducted, we have arrested more than 1,000 illegal immigrants from over 7,000 who were inspected."

Ops Mega 3.0 is a crackdown against illegal immigrants, launched on August 31.

"We do not want to compromise on the issue of illegal immigrants... because there are many other problems that will arise from this, for example, in relation to health issues and drug abuse," said the immigration department boss.

Meanwhile, commenting on the operation carried out at the Sepanggar and Kota Kinabalu areas from midnight to 4:00am yesterday (Malaysian time), Mustafar said 58 illegal immigrants were detained.

"This operation will continue throughout the country, and we want our country to be free of illegal immigrants," he added.

The major crackdown beginning on September 1 drew criticisms from the rights groups who demanded halt to it, arguing that most of the migrants were victims of exploitation or trafficking.

There are some one million Bangladeshi migrants, and nearly 50 percent of those are estimated to be undocumented, an official of Bangladesh High Commission in Kuala Lumpur told this newspaper earlier.