In the message, he also sympathized with the bereaved families of the victims and the Iranian people.
The message bears heartfelt condolences of the Singaporean people, he said.
'The attacks have shocked me and I would like to express condolences on behalf of people in Singapore to the Iranian nation as well as bereaved families of the victims,' he said.
“ Our thoughts and prayers will be with the Iranian people at this sensitive juncture,' he said.
Singapore’s foreign ministry also condemned the attack earlier this day.
Two terrorist groups attacked mausoleum of the late Imam Khomenini, southern Tehran, and the Iranian Parliament (Majlis) on Wednesday morning, killing 17 people and injuring 52 others.
One of the attackers blew up himself outside Imam Khomeini shrine.
The terrorist group of Daesh (ISIS) has claimed responsibility for the fatal attacks in Tehran.
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Publish Date: 8 June 2017 - 18:35
Kuala Lumpur, June 8, IRNA -- Singapore President Tony Tan on Thursday cabled a message to President Hassan Rouhani to condemn terrorist attacks in Tehran which claimed lives of many innocent people.