Rioters in Hong Kong's Tuen Mun area used corrosive liquid in a new round of protests on Tuesday, injuring multiple police officers and reporters.

Hong Kong police posted pictures on Twitter showing officers' wounds and clothes that were damaged by liquid.

"The Police strongly condemn the violent acts and appeal to members of the public to mind their personal safety," the police said on Twitter. 

An notice of objection has already been issued for Tuesday's rally after a public safety risk assessment, police said at Monday's media briefing, noting that the violence could "further escalate" in the day.

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From around 1:00 p.m. on Tuesday, radical protesters have been carrying out violent acts in several locations, including Hennessy Road, Admiralty, Tuen Mun and Wong Tai Sin, building barricades, blocking roads, paralyzing traffic and damaging public property. 

Police are now carrying out dispersal operations with tear gas and other appropriate force after warnings were ignored.

CGTN confirmed with Hong Kong Hospital Authority that as of 5:00 p.m. local time on Tuesday, 13 people remain hospitalized and two have been discharged.

Among those still in hospital, 12 are in stable condition and one man is in critical condition. The Hospital Authority has not yet determined how the man got injured.