Afghan security forces arrested a Pakistani intelligence officer in the east of the country, a presidential spokesman said on Tuesday, a day after an army general was arrested for alleged espionage.
The man's arrest on Tuesday in troubled Kunar province bordering Pakistan comes amid a row between the two allies in the US-led "war on terror" over Islamabad's alleged efforts to destabilise Afghanistan.
"A Pakistani national currently working as an officer for ISI (Inter-Services Intelligence, the Pakistani spy agency) was arrested with convincing documents," Mohammad Karim Rahimi, the spokesman for President Hamid Karzai, told a weekly briefing.
Rahimi gave no further details about the arrest and said the case was under investigation.
A senior government official at the presidential palace named the Pakistani as Sayed Akbar and said he had confessed to having contacts with "high-ranking" ISI officers in neighbouring Nuristan province.
Akbar had been in Kunar since 2004 pretending to work as an assistant to a local Afghan doctor, the official told on condition of anonymity.
Pakistan said Kabul had not informed it about the arrest of any Pakistani national.