MANILA, Philippines – Liberal Party stalwarts and candidates, led by standard-bearer Sen. Benigno Aquino III and his running mate Sen. Mar Roxas, have expressed concerns on the preparations of the Commission on Elections (Comelec) for the May 10 polls.

LP vice president and general campaign manager Butch Abad said one of the alarming issues is not allowing the review of the source code to be put in the PCOS machines.

"There is no way of knowing what's in the machines," Abad told a media briefing this morning at the LP headquarters in Cubao, Quezon City.

The source code, he said, is the brains of the counting machines.

Abad said another concern is the deletion of the ultraviolet or security marking on the official ballot. The original marking has been replaced by the marking of the National Printing Office, he added.

Abad said doing away with the ultraviolet marking and using a manual scanner would need more time.

"With the very limited time for voting, the use of the manual scanners will make it even more limited," he said.

He also noted that manual scanners would not recognize bogus ballots from the genuine ones.