The number of travelers who made visa-free entries through Jeju Island and overstayed in Korea increased by about 18 percent in the first seven months of this year.

As of the end of July, 11,979 migrants who overstayed after entering Jeju Island without visas were remaining in the country, up 2,133 from December last year, according to Ministry of Justice data released Tuesday by Rep. Lee Eun-jae of the opposition Liberty Korea Party.

Last year, 2,058 migrants overstayed the period of time they are allowed to stay after entering through Jeju Island without visas. Foreign travelers can stay visa-free only within Jeju Island.

If this trend continues, the number of people who entered Jeju Island visa-free and overstayed is expected to increase by over 3,600 this year.

The year 2016 saw the highest annual increase of such migrants overstaying, at 2,875.

In the January-July period this year, immigration authorities nabbed 127 foreign nationals who entered Jeju Island and left or attempted to leave the island to go to other parts of Korea without visas. The figure translates into a monthly average of 18.1 people, similar to 18.5 in 2016 and 15.7 in 2017.

“We must do better to find violators and keep them under control, and deal with legal loopholes in order to keep the visa-free system from being misused as a means of human smuggling,” Rep. Lee said.

By Kim So-hyun (sophie@heraldcorp.com)