Security staff stand on guard outside the St. Anthony's Church where a blast took place in Colombo, Sri Lanka, April 21, 2019. (Xinhua/A.Hapuarachchi)

by Xinhua writers Dan Ran, Zhu Ruiqing and Tang Lu

COLOMBO, April 22 (Xinhua) -- Sri Lanka was plunged into shock and grief over the weekend, as a string of deadly bombings rocked churches and hotels across the country on Sunday, killing nearly 300 people and injuring nearly 500, in the worst acts of violence since the country's civil war ended in 2009.

At least eight blasts were reported during the day, six in the morning, in quick succession, and two in the afternoon.

So far 290 people, including over 30 foreigners, have been confirmed dead and over 450 were injured.

Sri Lankan Prime Minister Ranil Wickremesinghe on Sunday called upon people to remain "united and strong" during the "tragic time."

WORST BLOODSHED SINCE END OF CIVIL WAR

Sunday's attacks were the worst acts of violence since the country's nearly 30-year civil war between government troops and the Tamil Tiger rebels ended in 2009.

Police spokesperson SP Ruwan Gunasekara said two explosions were reported from St. Anthony's Church in Kochchikade in capital Colombo. One struck St. Sebastian's Church in Negombo on the outskirts of Colombo, while another one was reported from a church in the eastern town of Batticaloa.

TV Footage showed panic-stricken people standing outside St. Sebastian's Church, where the explosion ripped off the roof and knocked out the doors and windows with broken glass strewn on the street.

Following the church blasts, explosions ripped through three high-end hotels located in the heart of the capital -- the Cinnamon Grand, Shangri-La and Kingsbury hotels.

Hours later, a seventh explosion happened from opposite the Dehiwala Zoo in Colombo, followed by an eighth one moments later, police said.

State Minister of Defense Ruwan Wijewardene said Sunday that most of the attacks were carried out by suicide bombers.

There has been no claim of responsibility so far for the deadly attacks.

"I strongly condemn the cowardly attacks on our people today. I call upon all Sri Lankans during this tragic time to remain united and strong," Wickremesinghe said on Twitter Sunday.

Sri Lankan President Maithripala Sirisena issued a statement Sunday calling for people to remain calm and support the authorities in their investigations, and called a meeting of the National Security Council early on Monday.

POSSIBLE INTELLIGENCE BLUNDER

The six bombings on Sunday morning took place almost simultaneously, and the three luxury hotels under attack, all located in the heart of Colombo, were frequented by foreigners.

The country's Finance Minister Mangala Samaraweera said the attacks appeared to be a "well coordinated attempt to create murder, mayhem and anarchy."

Minister of Telecommunications, Foreign Employment and Sports Harin Fernando said on Twitter late Sunday that some intelligence officers were aware of the incident, and that "there was a delay in action."

Media reports also pointed to a nationwide alert made by the country's police chief to top officers 10 days before the bombings, but Prime Minister Wickremesinghe said the warning had not been acted upon and that the information had not been passed to him.

Sri Lankan police said Monday that investigations will be carried out to look into possible failure by intelligence services to react to early warnings.

"Sri Lanka has been clearly on the extremist threat," said Director General of the Institute of National Security Studies Asanga Abeyagoonasekera, who witnessed the attack at Shangri-la Hotel on Sunday.

"Our intelligence and specially military intelligence need to be further strengthened as terrorism requires a multinational, multi-jurisdictional and multi-intelligence sharing approach," he said.

So far 24 suspects, all Sri Lankan nationals, were arrested after the multiple blasts, and 10 of them were handed over to the Criminal Investigations Department. Search operations were underway to nab more suspects.

Security has since been beefed up across the country.

FRESH SECURITY CHALLENGE

Sunday's deadly attacks deeply shocked Sri Lanka, a country healing from a 30-year civil war that ended only a decade ago. Memories of years of bloodshed still linger with many Sri Lankans.

In recent years, the government has been working to establish a steady and long-lasting post-war reconciliation and to achieve economic recovery. Sporadic ethnic and religious violence did occur, but attacks of this scale have been extremely rare.

The island country, known as "a pearl in the Indian Ocean" and ranked No. 1 travel destination in 2019 by Lonely Planet, has been developing a robust tourism industry to support growth in the post-war era. But the multiple bombings might deal a heavy blow to its hard-earned recovery and pose fresh security challenge to the country.

According to Wayne Huang, principal of the East Auckland-based Institute of Commercial Education in New Zealand, the attacks were very likely to have been carefully planned with foreign links, judging from the timing and the scale.

He said the deadly terrorist attack on New Zealand mosques in March and the most recent one in Sri Lanka revealed the insufficiency in multinational intelligence cooperation in the fight against terrorism.

"The perpetrators aimed to gain influence through acts of extremist violence ... The international community needs to have a thorough understanding and reflect upon previous anti-terrorism strategies," said the expert.

In the wake of the violence, the Sri Lankan government on Sunday declared a nationwide overnight curfew which was lifted on Monday morning. It also imposed a temporary ban on social media to prevent the spread of false information.

"Many terrorists use social media platforms to spread evil thoughts and acts of crime ... Stricter supervision on social media is thus needed to ensure public safety," said Huang.

The deadly attacks were widely condemned across the world, as government and state leaders, including those from China, the United States, Russia, India, France and Britain, among others, offered condolences to the Sri Lankan people and government.

"We are a strong nation who were fighting terrorism and this year is the 10th year of post-war (period). As a nation we will collectively rise from this dark day," said Abeyagoonasekera.

(Xinhua reporter Lu Huaiqian in Wellington also contributed to this report.)

(Video reporters: Tang Lu, Zhu Ruiqin, Jiang Chao; Video editor: Liu Xiaorui)