Global Affairs Canada is warning Canadians in Sri Lanka to exercise a “high degree of caution” after a series of bombings on Sunday killed nearly 300 people and injured roughly 500 others.

The department posted a travel advisory Monday that warns the situation remains volatile.

The bombings targeted churches and hotels in the cities of Colombo, Negombo and Batticaloa on Easter Sunday.

United States and Sri Lankan officials believe the co-ordinated series of bombings was launched by Islamic extremists, though no group has claimed responsibility.

Canadian officials say others attacks could occur throughout the country. Local officials have declared a state of emergency and say a curfew could be imposed at any time.

Sri Lankan authorities have also temporarily blocked access to some social media.

There are currently no reports of Canadians among the estimated 39 foreigners killed in the explosions.