He was on his way to office when the gunmen opened fire at his car killing the driver. His driver, Syed Hashim Raza, was hit by bullets and died in hospital, police said.
The gunmen then kidnapped Solecki. Witnesses said the car rammed into a house after the driver was shot.
Senior officials reached the spot and police cordoned off the area. A search has been launched for the UN official.
A spokesperson for UNHCR said investigations into the incident were underway. Security at the offices of UN organisations and foreign NGOs, which is already very high, was beefed up further after the incident.
Terror groups, baloch nationalist groups and Taliban are active in Balochistan.
OneIndia News (With inputs from Agencies)