South Korea’s foreign ministry said on Monday that South Korean nationals have been arrested in Iran on suspicion of smuggling, adding its embassy is in contact with Iranian authorities and providing consular assistance.

The ministry declined to confirm how many were detained or give details of their occupations or the alleged offenses.

South Korean media outlet Yonhap, citing diplomatic sources, reported that two South Koreans and an Iranian national were taken into custody around November 20 in Iran’s southwest on smuggling charges.

One of the South Koreans was described as an employee of a Korean public institution and the other a Korean resident in Iran, Yonhap said.

It added that Seoul officials have been liaising with Iran since the incident and are offering consular support.

The South Korean ministry said it could not disclose further information while the case remains under investigation by Iranian authorities.