The US has warned that the terrorist threat in Sri Lanka still remains as members of the group that carried out the attacks may still be at large. The US Embassy said that at the request of the Sri Lankan government, US security experts were working closely with the Sri Lankan partners on "fulfilling short term, specific objectives" related to the attacks.

from Times of India https://timesofindia.indiatimes.com/world/south-asia/us-warns-of-more-attacks-in-sri-lanka-by-active-members-of-terror-group-still-at-large/articleshow/69115768.cms