The quite distinctive Blue-tailed Bee-eater (Merops philippinus) is green overall with an orange-chestnut lower throat, black eyestripe and bluish rump/tail with long tail-streamers. 
The juvenile has a duller lower throat and lacks tail-streamers.
The bird is migratory and has a patchy breeding distribution across India, Myanmar, and parts of Southeast Asia but it can be seen throughout Singapore during the winter months.
The Blue-tailed Bee-eater and the Blue-throated Bee-eater (Merops viridis) are the only bee-eaters species found in Singapore.

A juvenile. Pasir Ris Park, Singapore, 24 October 2022