MANILA, Philippines — A condiments firm on Friday said that the already-tense situation at its factory where several workers mounted a picket was "aggravated" when members of a militant urban poor group threw rocks at policemen.

On Thursday, four workers were arrested when police dispersed a picket in front of the Marilao, Bulacan factory of condiments company NutriAsia.

The dispersal was prompted by a temporary restraining order that the Bulacan regional trial court issued against the striking workers.

The violent dispersal drew widespread condemnation especially from left-wing organizations.

According to NutriAsia, the protesters initially agreed to break their picket to allow the factory to resume its operations and just asked to be given an hour to do so.

However, instead of peacefully dispersing, the protesters staged a lie-in protest in front of the factory's gate and refused to voluntarily disperse despite negotiations with the sheriff.

"The situation was further aggravated when militant group Kadamay arrived at the scene and started to hurl rocks at the police," NutriAsia said in a statement.

The company said that the protesters also refused to attend two dialogues with B-Mirk Enterprises, which NutriAsia said was the employer of the picketing workers, organized by the National Mediation and Conciliation Board on June 4 and June 11.

"We join B-Mirk Enterprises in appealing to their employees to resume dialogues with their rightful employer at the proper venue made available to them by the National Mediation and Conciliation Board (NMCB)," the company said.

The condiments firm said that it respected and recognized the right to peaceful assembly of the workers and was just asking to regain free and safe access to its facilities.

"NAI hopes that the issue between B-Mirk Enterprises and its workers will be resolved soon," it said.

Members of the so-called Makabayan group of lawmakers in the House are seeking a congressional probe into the dispersal of the protesting workers.

"Didn't President Duterte himself say that he would eradicate Endo (end-of-contract) and contractualization?" the lawmakers said, referring to a campaign promise that the palace has said has already been fulfilled through an executive order signed on Labor Day.

The palace said in May that a complete ban on contractual labor could only be done through Congress.

Before yesterday's dispersal, the workers were blocking the entrace and exit of the factory since June 2.