Security forces in Mozambique waging the fight against jihadists in the country's north are guilty of "serious abuses" of human rights including summary executions, Human Rights Watch said on Tuesday.The group said that witness statements gathered since August proved police had carried out dozens of executions and arbitrarily detained people suspected of participating in the insurgency that has claimed dozens of lives."The Mozambican authorities should take immediate action to end abuses by their security forces and punish those responsible," said Dewa Mavhinga, Southern Africa director at Human Rights Watch. Jihadist fighters have terrorised remote communities in the gas-rich and Muslim-majority Cabo Delgado region for more than a year, staging brazen gun and knife attacks on civilians.Officials refuse to publish a death toll but according to local and media estimates, more than a hundred civilians have been killed in the clashes and thousands have fled the area.Twelve people are understood to have died just over a week ago in an attack blamed on jihadists that targeted a village close to the Tanzanian border.Analysts say the nascent insurgency staged its first attack in October 2017 hitting a police station and military outpost in the northern town of Mocimboa da Praia, killing two officers.Originally known as Ahlu Sunnah Wa-Jama - Arabic for "followers of the prophet" - the group is commonly referred to by locals and officials as "Al-Shabaab," although it has no known link to the Somali jihadist group of the same name.* Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and Facebook. President Filipe Nyusi has deployed heavy reinforcements to the region and vowed to eradicate the extremist group."Abuses by insurgents never justify violating people's rights, and the security forces should be protecting the people in Cabo Delgado, not abusing them," added Mavhinga. One suspect was rounded up with several other men in the regional town of Palma on August 18, two days after a suspected insurgent attack on a security forces base."There were many others there," said one of the men, a 23-year-old farmer. "We were all told to remove our shirts and sit on the floor. The soldiers would come and take us one by one to the forest, and then we would hear gunshots followed by screaming. Some of them did not come back." Two soldiers confirmed to HRW that troops had killed suspects but declined to give details. National police spokesperson Inacio Dina told HRW that "any person found to be engaging in suspicious activities in the regions attacked by armed groups is handed over to the police".Legal proceedings began against some 200 suspected jihadists at a jail in Pemba at the beginning of October.