KUALA LUMPUR (Reuters) - Arsonists attacked at least three churches in Malaysia early on Friday, prompting tighter police checks at churches nationwide ahead of mass demonstrations in a row over the use of the word ‘’Allah’’ for the Christian God.

Protests were due to take place later in the day to denounce a court ruling last week in predominantly Muslim Malaysia allowing the Catholic Herald newspaper to use ‘’Allah’’ in its Malay-language publication.

The impact on Malaysia’s financial market has been muted, but analysts said the issue could pose a longer term risk of political instability for Malaysia, which has been trailing Indonesia and Thailand for foreign investment.

A fire at the Metro Tabernacle church in suburban Kuala Lumpur, part of a Pentecostal group called “The Assemblies of God,” gutted a ground-floor administrative office.

Firebombs were later tossed into the compound of at least two more churches – the Assumption Catholic Church and the Life Chapel Protestant church – in the leafy outlying district of Petaling Jaya, but both failed to explode.

Police ordered tightened security at churches throughout the country and called for the cancellation of protests, due to take place after Friday prayers at mosques.

“Since last night, I have instructed all patrol cars to patrol all church areas. We are monitoring all churches,” Musa Hassan, Inspector-General of Police, told Reuters.

“I have advised them (protesters) to let this be handled by the court. I will take action against anyone who acts to jeopardize national security.”

Prime Minister Najib Razak’s ruling coalition suffered its worst defeats in the 2008 general election due in part to unhappiness by the mainly Chinese and Indian ethnic minorities over increasing Islamization and failed reform pledges.