It was the evening of April 8 when the Wong family's two dogs started barking frantically, alerting them to the presence of a 1.5m black spitting cobra in their backyard.

"We tried to stop our dogs from attacking the cobra and grabbed garden tools to intercept," said Mr Wong Ji Siang, 25 .

He lives with his mum and dad, aged 58 and 60 respectively, and 28-year-old sister in Carmichael Road, off Braddell Road, in a bungalow surrounded by lush vegetation.

By the time the family got the tools, the snake was already half dead and one of their dogs - a six-year-old female mongrel called Yeogi - had already been struck in its right eye by the spitting cobra's venom.

Their other mongrel, a six-year-old male called Kumar, was unharmed.

Yeogi has since regained most of its eyesight after a visit to the vet.

Mr Wong's father, Mr Donald Wong, told Shin Min Daily News: "The dogs are the guardians of our family. We will treasure them even more now."

The family said that the incident was not the first of its kind.

Just the previous morning, on April 7, the dogs had encountered another cobra but had killed it before any harm was done.

On many other occasions, creatures such as a civet cat and a python have entered their home.

Asked how residents should approach a snake or other creatures that enter their home, Ms Anbarasi Boopal, deputy chief executive of Animal Concerns Research and Education Society (Acres), said that they should call the 24-hour Acres hotline on 9783-7782 for help.

She said: "We will ask for a description of the snake or creature and provide further help. If the snake is solid black with no patterns, it could be a cobra and people should stay at least two metres away."

An earlier version of the story incorrectly identified Ms Anbarasi Boopal as Mr Anbarasi Boopal. We are sorry for the error.