KUWAIT - Kuwaiti security forces appear to have used excessive force to disperse several largely peaceful street protests since October, Human Rights Watch (HRW) said on Thursday, citing activists, protesters and witnesses. Tens of thousands of Kuwaitis have taken to the streets over the past two months to protest changes to voting rules used in a parliamentary election on December 1 that they said would skew the outcome in favor of pro-government candidates. The Interior Ministry justified the use of force on the grounds that protesters had blocked traffic, thrown stones at the police, and attacked them, HRW said. But participants said the demonstrations were largely peaceful. "They said that masked riot police used tear gas and sound bombs without warning to disperse demonstrations and beat protesters while arresting them for participating in 'unauthorized protests,'" the New York-based rights group said. Kuwait's Information Ministry, in reaction to the HRW statement, said authorities were required to maintain law and order when illegal marches and demonstrations took place. "Kuwait has witnessed several protests in 2012 where streets were blocked and riots took place at residential areas which endangered civilians and public properties," the ministry said. "The right to protest is enshrined in our constitution. However, protesters should be aware of both their rights and responsibilities under the law." Although Kuwait, an OPEC member state and ally of the United States, tolerates more dissent than other Gulf Arab countries, it has been enforcing a ban on public gatherings of more than 20 people without a permit. "Kuwait's rulers need to fully respect the right to assemble peacefully," Eric Goldstein, deputy Middle East director at HRW said in the statement issued from Beirut. "Declaring a gathering 'unauthorized' does not give police license to beat protesters."