Officials in Sri Lanka had received warnings about an upcoming attack weeks before the Easter suicide bombings that killed more than 300 people. The attacks were reportedly revenge for the Christchurch mosque shootings.
Security forces arrested 40 people over a series of terror strikes in Sri Lanka, including the driver of a van allegedly used by suicide bombers, officials said on Tuesday. An owner of the house where some suspected attackers lived was also detained.
The six near-simultaneous blasts targeted three luxury hotels and one church in the capital Colombo, and two more churches in two other Sri Lankan cities on Easter Sunday. Authorities in the Buddhist-majority country believe the local Islamist group National Thowfeek Jamaath was behind the attacks, presumably with international terror networks providing "support."
The militant group was apparently motivated by the shooting attacks on mosques in New Zealand, officials said.
"The preliminary investigations have revealed that what happened in Sri Lanka was in retaliation for the attack against Muslims in Christchurch," state minister of defence Ruwan Wijewardene told lawmakers on Tuesday.
The police are holding a Syrian in custody for questioning over the attack, an unnamed source told the Reuters news agency.
Interpol investigators on the way
On Tuesday, authorities upped the death toll to 310, saying that more people have died of their injuries since the attack. Another 500 people remained in hospital.
Sri Lankan authorities lowered flags at half mast and held a three-minute silence to start a day of national mourning for the victims on Tuesday.
Interpol said they were sending in their investigators and specialists to Sri Lanka to help with the investigation.