The culprits behind the multi-billion-peso collapse of the Cabagan-Sta. Maria Bridge in Isabela, including officials from the Department of Public Works and Highways, must be held accountable for the blunder and serve jail time, senatorial aspirant Erwin Tulfo suggested Sunday.

Tulfo, renowned for being a hard-hitting journalist, lamented that the public funds earmarked for the construction of the bridge were obviously corrupted, as evidenced by the use of "substandard" materials.

“It is crystal clear that the collapsed Cabagan-Sta. Maria Bridge in Isabela was done cheaply so someone could pocket the excess funds from the project,” the lawmaker said in an interview.

President Ferdinand "Bongbong" Marcos Jr. disclosed that the funding for the bridge was initially set at P1.8 billion but was eventually trimmed down to P900 million before it ballooned to P1.2 billion due to retrofitting.

The construction of the bridge dates back to 2014 during the administration of late former president Benigno Aquino III. However, 90 percent of the construction was finished during the Duterte administration, according to Presidential Communications Undersecretary Claire Castro.

The government took more than a decade to construct the 900-meter bridge, only for it to be compromised after an attempted passage of three dump trucks carrying boulders and weighing about 102 tons.

A 60-meter part of the bridge collapsed on 27 February, merely 26 days after it was opened to the public.

During his visit last week, Marcos attributed the botched job to a "design flaw," without proper support for the arch and attached cables.

Tulfo, however, countered that there is no one to blame other than the engineers of the DPWH if the President's suspicion is correct.

"Look, P1 billion from the nation’s coffers were allocated for this bridge, only to be compromised. For what? Obviously, to increase the kickbacks of corrupt individuals who took advantage of it," the congressman pointed out.

“There were even reports of design errors, yet the DPWH still allowed the contractors to proceed with the construction. Why is that?" he added.

During a sortie last week, Tulfo implied that the country has ceaseless road and infrastructure projects because of a "large kickback" in them.

He asserted that imprisonment is highly necessary for cases like this to deter others from engaging in corrupt practices.

“The contractor must have bribed the DPWH inspectors and supervisors, blinding them to the project’s non-compliance with government standards," Tulfo alleged.

Earlier, Marcos warned that heads would roll if the ongoing investigation confirms their suspicions that corruption was involved in the bridge's construction.