The Immigration and Checkpoints Authority (ICA) was rapped by Deputy Prime Minister Teo Chee Hean on Sunday for a second checkpoint breach in two months.
On Saturday, a 64-year-old Singapore permanent resident drove a car over a security barrier at the Woodlands Checkpoint at 4.05pm, sparking a manhunt which ended with the man being nabbed five hours later at 9.15pm.
The police said on Sunday that the man is under investigation for "a package suspected to contain drugs". Two of his Singaporean associates were picked up by the police, and two Malaysians were stopped from leaving Singapore. The four are now helping with investigations, police said.
The failure of the security barrier to stop the car - a 24-year-old Mercedes-Benz sedan - drew a sharp rebuke from DPM Teo.
Referring to a breach at the same checkpoint on January 17, when a Malaysian teacher slipped past officers by tailgating a car, Mr Teo said the latest case reinforces the findings of a review which showed that "the alarm and barrier systems at the checkpoints are inadequate, and they need to be improved and strengthened considerably".
The procedures and training also need to be "improved sharply", he said in a statement.
Mr Teo, who is also the Home Affairs Minister overseeing the ICA, added: "I have directed the commissioner of the ICA to implement measures to better secure our checkpoints as soon as possible."
The commissioner "will also review if there are further enhancements needed" after the latest breach.
Mr Teo noted that the police had followed standard operating procedures by putting out an "immediate alert", and roping in taxi drivers to look for the car and driver. The Criminal Investigation Department was also activated.
"Police will study whether further improvements can be made in tracking down such cases."
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