Debra Lobo who was working as the vice-principal of the Jinnah Medical and Dental College's student affairs wing was attacked on the busy Shaheed-e-Millat Road and was rushed to hospital where doctors are trying to save her life.
Police said that Lobo was attacked by four unidentified gunmen as she left the college premises.
The American national from California left her college in the afternoon for her home when four gunmen shot her twice in the cheek and shoulder. Lobo is an associate professor of community medicine.
Police said armed gunmen opened fire on Aijaz Khawaja while he was in his car and was severely injured. He later succumbed to his injuries.
Target killings, kidnappings, extortion and street crime have become a menace in Pakistan's biggest city and the fresh round of target killings come just as the paramilitary rangers claim to have stepped up and gained success in its operation against terrorists and criminals and organised crime lords.
According to police records 2,029 people were murdered on the streets of Karachi in 2014.