KUALA LUMPUR (Reuters) - Malaysian police said on Tuesday they have arrested seven people, including four foreigners, for suspected links to the Islamic State (IS) militant group and for planning attacks in Malaysia and abroad.

Authorities in Muslim-majority Malaysia have revoked the passports of scores of citizens identified as having left the country to join Islamic State and police reported this year that 18 Malaysians had been killed fighting for the group in Syria, and another seven were killed carrying out suicide attacks.

A grenade attack on a bar on the outskirts of the Malaysian capital, Kuala Lumpur, in June was the Islamist group’s first successful assault in the country.

Police said in a statement their latest arrests were made between Nov. 3 and Dec. 16.

One foreigner was arrested for suspected links to IS and attempting to get details about security at international school in Kuala Lumpur, while another was detained for helping him.

Both were enrolled as students at a university near the capital, police said.

A third arrested foreigner had been detained in the Middle East in 2010 under suspicion of being involved with al Qaeda, police said.

Another foreign national suspected of having links to IS tried to smuggle firearms into Indonesia, and also attempted to sneak into Myanmar to launch an attack, Malaysian authorities said.

The identity and nationality of the foreigners were not disclosed.

Three Malaysians were detained for planning attacks in the country or for suspected IS links, police said in the statement.

One of them was getting orders from Muhammad Wanndy Muhammad Jedi - a Malaysian known by police to be fighting with Islamic State in Syria - and was planning attacks on places of entertainment in Kuala Lumpur and the city of Malacca, police said.

Malaysia has made several arrests before, including of supporters of IS who were suspected of planning attacks in the capital ahead of independence day celebrations.

Authorities in Malaysia have been on high alert since Islamic State-linked militants carried out a attack in the capital of neighboring Indonesia in January.