By CCN.com: The US State Department has published a new travel advisory warning that more suicide bombings could be on the way in Sri Lanka. It comes after 290 victims were killed in terrorist attacks across the country on Easter Sunday.

Per a Reuters report, the State Department warned that terrorists are still active in the region:

“Terrorists may attack with little or no warning.”

US citizens in Sri Lanka are advised to avoid crowded areas and adhere to the curfew which now extends to 4am on Tuesday morning.

Terrorist Targets: Airports, Hotels, Tourist Locations

The State Department travel advisory, updated on Sunday, outlines various possible terrorist targets. The list cites airports, transport hubs, churches, other places of worship, shopping malls, tourist locations, and public areas.

Horrible scene from the Easter Sunday terrorist attacks today in Sri Lanka.#SriLanka pic.twitter.com/9wY6CQWlWN — Noorullah kHan (@Noorull29231054) April 21, 2019

It comes after terrorists struck multiple churches and luxury hotels in a coordinated attack across the country this weekend. The death toll currently stands at 290, with at least 500 injured.

Three churches were targeted in Batticaloa, Negombo, and Colombo’s Kochchikade district. Sri Lanka’s capital was also rocked by three explosions at the Shangri-La, Cinnamon Grand, and Kingsbury and hotels. Two further explosions took place later in the day.

Easter is a time of rebirth & joy for Christians – but extremists brought terror & violence to people at churches in #SriLanka today. I am praying for the victims’ families as they mourn. Though we grieve today, terrorists can never take away our faith or love for one another. 🇱🇰 — Malala (@Malala) April 21, 2019

Who Carried Out the Vicious Terrorist Attacks?

The attacks were all linked to suicide bombers, and believed to be orchestrated by an Islamic terrorist faction, National Thowheed Jamath.

The Sri Lankan government referred to the group as a “radical extremist Islamist group.” At the time of writing, 24 suspects have been arrested in connection to the Easter Sunday massacre.

Sri Lanka has blamed local jihadist group National Thowheed Jamath for one of Asia’s deadliest terrorist attacks in years. Here's what we know about the Easter Sunday blasts: pic.twitter.com/BmAGYi3Yb9 — Bloomberg QuickTake (@QuickTake) April 22, 2019

A Sri Lankan cabinet spokesperson, Rajitha Senaratne, said the attacks were likely part of an international effort:

“We do not believe these attacks were carried out by a group of people who were confined to this country. There was an international network without which these attacks could not have succeeded.”

The U.S. condemns in the strongest terms the Easter morning terror attacks in Sri Lanka. These attacks demonstrate the brutal nature of terrorists whose sole aim is to threaten peace & security. We offer our deepest condolences and stand with the government & people of #SriLanka. — Secretary Pompeo (@SecPompeo) April 21, 2019

“Massive Intelligence Failure”?

It is believed that Sri Lankan police authorities warned the government of the imminent attacks ten days prior to the deadly bombings.

On April 11, Sri Lanka police chief Pujuth Jayasundara sent an intelligence warning (See Image) to top officers that National Thowheeth Jama’ath, a Muslim jihad group, plans to attack churches on Easter. Attack Death Toll spikes to 290, about 500 injured https://t.co/YCXSDrMxLK pic.twitter.com/XxDSEkQb1D — Adam Milstein (@AdamMilstein) April 22, 2019

According to a report in The Sun newspaper, police chief Pujuth Jayasundara told officials before the attacks:

“A foreign intelligence agency has reported that the NTJ (National Thowheeth Jama’ath) is planning to carry out suicide attacks targeting prominent churches as well as the Indian high commission in Colombo.”

Senaratne admitted the police had received prior warning, and the government has reported admitted “massive intelligence failures” for failing to heed advice.

Billionaire’s Family Among the Victims

The 290 victims are predominantly Sri Lankan. However, 35 foreigners are believed to be among the dead. Of them, three are confirmed to be the children of Danish billionaire and largest Asos shareholder Anders Holch Povlsen.

Five British citizens and six Indians are also among the confirmed victims at the time of writing.