Singapore shares crashed on Thursday, mirroring regional declines as Asian markets reacted negatively to the possibility of the US getting involved in the Iran-Israel conflict.

STI fell 0.7%; SingPost up 1%; Nio fell 3%; Seatrium fell 2.4%; Sembcorp fell 2%; Keppel fell 1.6%; UOL, SATS fell 1.3%.

The Straits Times Index (STI), a key benchmark for the Singapore Exchange, ranged between 3,892.09 and 3,917.62 throughout the day. It ended the session at 3,894.18, down 26.63 points or 0.68% compared to Wednesday's close.

In company news, shares of Seatrium (SGX:5E2) were down over 2% after it signed a letter of intent with Norwegian maritime solutions provider Solvang for the installation and retrofitting of full-scale carbon capture and storage systems.

SATS (SGX:S58) shares were down over 1% as its subsidiary World Flight Services launched and priced $100.0 million worth of 4.648% fixed rate bonds due June 23, 2030, under its $3 billion multicurrency debt issuance program.

Meanwhile, shares of RH PetroGas (SGX:T13) were up nearly 4% at the close with the company set to issue and allot 540,000 new shares in its capital at SG$0.15 per share under its RHP Share Option Scheme.