When Mr Kalam Mohd Abu's wife saw a picture of him with police officers on Facebook, she thought he had done "something wrong".

But it was quite the opposite.

On Sunday, the Bangladeshi cleaner was working in Commonwealth Crescent when a woman in a sixth-storey flat asked him for food.

Without hesitation, the 31-year-old said she could have the curry and rice that he had prepared at his dormitory the night before.

His act of kindness was noticed by some police officers who were on patrol.

They were so impressed that they took pictures with him and posted them on Facebook.

The post garnered hundreds of "likes" and on Wednesday, he was awarded a certificate of appreciation by Tanjong Pagar Town Council.

Mr Kalam also won praise from his wife and family in Bangladesh.

"She thought the police had caught me, that I did something wrong," said Mr Kalam, who has been working in Tanjong Pagar since he came to Singapore a decade ago. "But I said no, nothing wrong. This one's happy news."

The woman he helped just had an operation and was not very mobile. "She cannot cook, cannot go to the market to buy (food)," he added.

Mr Kalam earns less than $1,000 a month but said he is "very happy" to be working in Singapore.

He spoke no English when he arrived here, but now speaks some, a little Malay and even Singlish.

He sends money back to his parents, wife, and two-year-old daughter, whom he has yet to meet.

Mr Kalam's supervisor, who declined to be named, said that this is not the first time Mr Kalam has given food to an elderly resident in the area.

"He has already been giving extra food to the elderly. That's why when the woman asked for food, his instincts kicked in. They're also comfortable eating the food because they already know him."