A senior Pakistan navy officer was shot dead and his Swedish wife wounded in Pakistan's port city of Karachi on Wednesday, police said.

The couple were shot on a busy thoroughfare near the National Stadium.

Two gunmen riding a motorbike intercepted Captain Nadeem's vehicle and opened fire, killing him on the spot, a local police official told AFP.

Nadeem's wife sustained a bullet injury in the attack and has been taken to a naval hospital, he added.

Nadeem taught at the Karachi campus of the National University of Sciences and Technology.

A naval intelligence official also confirmed the killing.

There was no immediate claim of responsibility for the attack.

Earlier on Feb 27, a lieutenant commander of the Pakistan Navy was wounded in an attack in Karachi’s Keamari area. He later succumbed to his injuries.

In another incident on Feb 7 a naval officer and his wife were injured in a mysterious explosion in their car near the city’s Karsaz area.

Moreover, in May 2011, Taliban militants raided a naval base in the city, destroying two P-3C Orion surveillance planes and killing 10 personnel in a 17-hour assault.

Karachi, which is Pakistan's largest city, is suffering from an unprecedented wave of killings and kidnappings blamed on militants, criminals, and ethnic and political tensions.

Gang wars fed by ethnic and political bitterness, drugs and the Taliban, have created a culture of impunity in the city of 18 million, and the past two years have seen record death tolls.

In the first six months of 2013, 1,726 people were killed compared with a previous high of 1,215 in the same period last year, according to the Human Rights Commission of Pakistan.