The long weekend may have drawn 1.7 million people to the various SG50 activities, but it also meant more work for a group of specially trained policemen - the dog handlers and their working dogs in the Police K-9 unit .

More than 40 dogs from the Police K-9 unit were deployed across the island, about 20 per cent more than usual, from the airport to land checkpoints and ferry terminals, said the police.

The dogs' job: Sniff out drugs, firearms and bombs to keep Singapore safe, as Singaporeans partied to celebrate the nation's birthday over the long weekend.

They did patrols at MRT stations and bus interchanges and conducted bomb sweeps at various public places where Golden Jubilee celebrations were held.

At Bedok MRT station, newly minted police dog Buster walked up and down the platform with his handler, Staff Sergeant Png Lee Kun, stopping occasionally to sniff passengers' bags that have piqued his curiosity.

The British-born border collie and labrador cross-breed completed a three-month explosives detection course in April. He is one of 10 police dogs in the team that patrol the public transport network daily.

"He is not afraid of crowds," said Staff Sgt Png.

The pair work 12-hour shifts daily for five days and get two days off in between. "Having had to work this long weekend, there has been no break for us," she said.

At Tuas and Woodlands land checkpoints, the dogs and their handlers, on top of their usual duties, are also exposed to the exhaust fumes of the vehicles.

One of those taking on the tough assignment at Tuas Checkpoint over the long weekend was seven- year-old labrador Brad and his handler, Staff Sergeant Teo Hong Ling.

"We check cars, buses and lorries entering Singapore," she said.

When asked whether she or Brad had missed having the long weekend, Staff Sgt Teo said with a smile: "For Brad, this is a working day. He does not know that this is a special weekend. For me, I am trained to do a job, so I will do my duty."

Toh Yong Chuan