(Adds detail, new attack in Logar)
KABUL Feb 24 (Reuters) - Afghan security forces shot dead at least one would-be suicide bomber on Sunday in a high-security area of Kabul, home to government departments and diplomatic missions, police said.
Violence across the country has increased over the last 12 months, sparking concern about how the 350,000-strong Afghan security forces will manage once most foreign troops withdraw by the end of 2014.
The attack, one of four in Afghanistan early on Sunday, happened near a construction site that was stormed by Taliban gunmen in April last year. That assault triggered a nine-hour attack in which the insurgents fired rockets at western embassies and nearby hotels frequented by foreigners.
The man shot dead on Sunday was in a stationary four-wheel-drive vehicle in the suburb of Sherpur when officers from the country's intelligence agency, National Directorate of Security (NDS) fired at the car, killing him.
The would-be bomber was carrying a gun and wearing an explosive-laden vest when he was shot dead, Kabul police chief General Ayoub Salangi told Reuters.
The car was also packed with explosives. Security forces were still attempting to defuse it an hour later.
The attack came on the same morning as bombings in the eastern provinces of Nangarhar and Logar.
In the capital of Nangarhar, Jalalabad, two NDS guards were killed and three others wounded when a car carrying explosives was detonated at a compound used by the intelligence agency.
In Logar an attacker detonated a van packed with explosives at a highway checkpoint, wounding three police officers.
Later on Sunday morning, a man in a suicide vest blew himself up outside a district police office, wounding another police officer.
No one has claimed responsibility for the Kabul incident but the Taliban took credit for the attacks in the eastern provinces via text message.
In January six suicide bombers attacked an NDS compound in downtown Kabul, killing two guards.
Less than a week later, attackers stormed the headquarters of Kabul's traffic police and engaged in an eight-hour gun battle with security forces before being killed.
(Reporting by Hamid Shalizi; Writing by Dylan Welch; Editing by Daniel Magnowski)