Fatima Salim, a teacher who was shot dead during the 2011 protests against military rule, was an activist who had helped found a Muslim association which had demanded that children be sent to mosques for prayer and public prayer had been introduced into schools.

She was also a regular contributor to Radio Azadi and was part of a group that went to Egypt’s interior ministry to complain about their education system.

“She was an activist for many years against religious and political prejudice,” said Omar al-Zarqawi, a spokesman for Libya’s new anti-terrorism court, speaking to The Telegraph, where he is an editor-in-chief.

“She was killed in the middle of her work for these victims.”

Image copyright Reuters Image caption Some 250 people were killed at Rabaa al-Adawiya mosque by masked militiamen in 2013

Image copyright Reuters Image caption Thousands of people have been killed and injured by Islamist fighters in Libya since the 2011 uprising

Image copyright EPA Image caption The country’s powerful and influential al-Qaeda branch, Ansar al-Sharia, is now the most active and powerful Islamist group

Tunisia’s deputy foreign minister Faisal Mekki called Mokhtar’s killing as a “grave act”, according to AFP news agency.

Ansar al-Sharia is now the most active and powerful Islamist group in the country, along with groups such as Islamic State.

In January, Ansar al-Sharia seized a small town in the south of the country and claimed responsibility for last week’s attack in Bardoa, where 32 people died.

The group has since claimed responsibility for other attacks including at four churches and a government building.