Burj Khalifa lights up in Sri Lankan flag colours to commemorate the attacks in Sri Lanka. Reuters

Burj Khalifa, the world's tallest skyscraper, lit with an image of Sri Lanka's national flag in solidarity with the country following the April 21 ‘terrorist’ attacks in hotels and churches celebrating Easter that killed more than 250 people.

The Burj Khalifa’s official page on Instagram said, “BurjKhalifa lights up in solidarity with #SriLanka. Here’s to a world built on tolerance and coexistence…”

His Highness Sheikh Mohammed Bin Rashid Al Maktoum, Vice President, Prime Minister and Ruler of Dubai, said on Twitter, “Terrorists are those who betray worshippers in their places of worship, plant fear in their hearts and try to ignite religious conflicts in societies. Our condolences to the people of Sri Lanka, to the world and to everyone who works tirelessly towards tolerance and coexistence.”

Meanwhile, Police in Sri Lanka have issued an appeal for information about three women and one man suspected of involvement in the Easter suicide bombings that killed over 350 people.

Police made the appeal on Thursday over Sri Lankan media.

They released pictures of the four. All appeared to be in their 20s.

Police did not elaborate on how the four may have been involved. However, police and soldiers tightened security across Colombo and elsewhere Thursday as fears of another attack continued.

They identified the suspects as Mohamed Shahid Abdul Haq, Fathima Latheefa, Abdul Cader Fathima Kadia and Pulasthini Rajendran, who also had the alias Zara.