Human Rights Watch accuses Houthis of cracking down on civil society and ‘disappearing’ political opponents.

Houthi rebel forces in Yemen have closed down dozens of non-governmental organisations and detained activists affiliated with a rival political party, according to a US-based rights group.

Many of the organisations were closed for their perceived connections to Islah, a rival political party, Human Rights Watch (HRW) said in a press release on Sunday.

HRW also said the Houthis had detained more than 100 Islah party members and activists.

At least 33 NGOs in the capital Sanaa have been closed since September 2014, according to statistics provided to the rights group by the United Nations Office of the High Commissioner for Human Rights.

Since March, a Saudi-led coalition has been fighting the Iranian-allied Houthis.

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“The Houthis’ closure of organisations comes in the midst of a campaign of arrests and enforced disappearances of activists, political opposition figures and journalists,” Joe Stork, deputy Middle East director, said in the statement.

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“This is one more repressive Houthi tactic to close down democratic space in the areas they control.”

Hussain al-Bukhaiti, a pro-Houthi activist in Sanaa, told Al Jazeera that the organisations closed belonged to Islah but that they were being used as weapons depots for groups fighting alongside the coalition.

“We’re in a war. In war in any place in the world, anyone who participates in the coalition’s aggression is considered a traitor,” he said.

Bukhaiti denied that people were arrested for opposing the Houthis and said people were detained for “action on the ground, including financial support to any side affiliated with the coalition”.

HRW called on the Houthis to “immediately allow non-governmental groups to operate freely, compensate groups whose offices were looted, and release activists being detained for peaceful conduct”.

The UN has documented that, as of November 18, an estimated 5,700 people, including 830 women and children, have been killed in the conflict.

On Saturday, the Houthis announced a week-long ceasefire date ahead of planned peace talks in Switzerland with the Yemeni government.