Warrnambool police Senior Sergeant Chris Asenjo said the man was arrested in Geelong on Friday morning.

He was already on bail charged with sex offences, including rape and sexual penetration of a child aged under 16 years.

"The Warrnambool police sexual offences and child abuse investigation team initiated a rapid investigation into allegations an alleged offender had made contact with and was intimidating a witness," he said.

"He was already on county court bail charged in January last year with the rape of a child.

"My understanding is that those matters are currently before the court."

Senior Sergeant Asenjo said it was claimed the man had communications with the alleged victim and the Warrnambool detectives went to Geelong to execute a search warrant.

The man was arrested, interviewed and charged with intimidating a witness, breaching an intervention order and committing an offence while on bail.

He appeared in Geelong court late Friday and was remanded in custody.

It is alleged the accused man made contact with the female complainant via social media.

Senior Sergeant Asenjo said the well-being of complainants was paramount for SOCIT members.

"The safety of alleged victims is given the highest priority," he said.

"After the alleged contact team members took swift action. This is very significant alleged offending on top of very serious matters."

Electronic devices were seized during the search warrant in Geelong and they will be forensics examined.

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