Gloucestershire Police Assistant Chief Constable Arman Mathieson said the searches aimed to find digital devices for analysis.
“The arrest of a serving officer on suspicion of such a serious offence will no doubt cause our communities concern, as it does everyone who works for Gloucestershire Police,” he added.
“The arrest has been made to allow for a prompt and effective investigation to take place and we must not draw any conclusions at this stage.”
It’s an offence under section 12 of the Terrorism Act to provide support for a proscribed terrorist group.
Harakat al-Muqawamah al-Islamiyyah, more commonly known as Hamas, has ruled Gaza since 2007. It was proscribed in its entirety in the UK in 2021.
The group was responsible for the 7 October 2023 attacks, which saw hundreds of gunmen enter southern Israel. About 1,200 people were killed and 251 others taken hostage.
Israel retaliated by launching a military campaign to destroy Hamas, during which more than 43,400 people have been killed in Gaza, according to the Hamas-run health ministry.
A week after the 7 October attacks, the government’s independent reviewer of terrorism warned speeches at pro-Palestinian rallies in the UK might have glorified terrorism.
“People need to know, if you glorify that you risk committing a really serious terrorism offence,” Jonathan Hall KC said at the time.
Then home secretary Suella Braverman also said “the full force of the law” should be used against support for Hamas.
Members of the Conservative government urged the Metropolitan Police to increase patrols, claiming people were “glorifying the terrorist activities of Hamas”.
In April this year, a man was found guilty of wearing a headband in support of Hamas at a pro-Palestinian rally in central London.