More than 50 people, mostly militants, have been killed in attacks and bombings across Afghanistan since Monday morning, authorities said Tuesday.At early Tuesday morning, five Afghan policemen and eight militants were killed when Taliban launched a coordinated attack on a police compound in Jalalabad city, the provincial capital of eastern Nangarhar province. \"Eight suicide bombers stormed the Fast-Reaction Police Force complex in Jalalabad at around 4:45 a.m. local time Tuesday. Two militants detonated two explosive-laden cars at the gate, one bomber detonated his explosive vest and five who tried to enter the facility were killed by police,\" the provincial government said in a statement.It said five other policemen were wounded in the attack in the city, 120 km east of Afghan capital Kabul.Following the blasts and gunfight, the Taliban insurgent group claimed responsibility for the incident.Zabihullah Mujahid, a Taliban purported spokesman, told local media via phone that the insurgents carried out the raid, killing scores of Afghan police and foreign trainers.The bombing came at the second day of visit of Kabul by U.S. Secretary of State John Kerry.On Monday evening, a total of 27 Taliban militants had been killed in a clash which broke out during a poppy-eradication camping in Garmser district in Helmand province 555 km south of Kabul, the provincial governor Mohammad Naim said Tuesday. \"An Afghan army officer and a policeman were also killed in the fighting lasting for hours,\"Naim told Xinhua, adding one cop was also wounded in the attack.The Taliban, who ruled the country before they were ousted by a U.S.-led invasion in late 2001, renewed armed insurgency, staging ambush and suicide attacks, killing combatants as well as civilians.In addition, up to 11 militants have been killed when army carried out a cleanup operation in Helmand\'s Marja district, said senior army official Gen. Seyyed Maluk.In neighboring Nad Ali district, an army soldier was wounded when a Taliban suicide bomber set off his explosive-laden truck near army outpost Monday night.Notorious for growing poppy and militancy, the Helmand province has been branded as Taliban stronghold in southern Afghan region.The insurgent group has warned the civilians to stay away from official gatherings, military convoys and centers regarded as the legitimate targets by militants besides warning people against supporting government and foreign troops.The latest bombings and attacks underscore the challenges that Afghan army and police faced as they struggle to provide security across the country before assuming the full operational lead in a couple of weeks and the departure of all U.S. and NATO forces by the end of next year.The Taliban-led insurgency and conflicts claimed the lives of 2, 800 Afghan security forces and over 400 foreign soldiers besides leaving 2,750 civilians dead last year in the central Asian state.