HARARE — Supporters of Zimbabwean President Robert Mugabe's party beat up a lawmaker and a journalist when they barged into a public hearing on a proposed human rights bill, media reports said on Sunday.

The private Standard newspaper said about 20 youth on Saturday mobbed and beat up Brian Tshuma, an MP from Prime Minister Morgan Tsvangirai's party, accusing him of not singing the national anthem at the start of the hearing.

"About 20 people descended on him, dragged him with his tie as they kicked and punched him while violently throwing him out of the parliamentary caucus room," the paper reported.

The mob later turned on Levy Mukarati, a reporter for the independent weekly Financial Gazette, accusing him and some counterparts of writing false stories.

The youth were also protesting that the bill had been written in English and not the local Shona language.

The bill is among reforms agreed to in a power-sharing agreement reached between Mugabe and Tsvangirai in the aftermath of disputed 2008 polls.

On Wednesday, police and youth from Mugabe's party blocked a meeting where US ambassador Charles Ray was supposed to talk with a group of young people.

Police had okayed the meeting in the mining town of Kwekwe but at the last minute revoked their decision, Ray said in a statement.

Militants overran the meeting, distributing flyers in support of Mugabe, a US embassy official told AFP.

Supporters of Mugabe's ZANU-PF party have repeatedly disrupted political meetings across the country, particularly targeting outreach programmes meant to gather views on a new constitution ahead of fresh elections.