The Islamic State group claimed responsibility for a wave of coordinated bombings at churches and high-end hotels across Sri Lanka, ABC News reports.

The terrorist organization made the claim Tuesday in a statement published in Arabic by its Amaq news agency, saying the attackers were "among the fighters of the Islamic State," according to a translation by SITE Intelligence Group, a company that tracks extremist groups.

Sri Lankan authorities have not confirmed that report.

At least 310 people were killed and another 500 were injured Sunday when near-simultaneous explosions took place at eight locations across the island nation, which is located off the southern tip of India.