Tunis: Tunisia’s largest union cancelled on Wednesday a general strike set for the next day, a move which could calm Islamist-leftist tensions after violent clashes in the capital.

The UGTT union announced the strike last week after several hundred Islamists armed with knives and sticks charged a union gathering and smashed office windows on December 4.

Police had to intervene to separate the two groups.

“The strike was cancelled because of a lack of security,” UGTT secretary-general Hussain Abassi said, without giving more details.

The moderate Islamist Al Nahda party won elections last year, following the 2010 ousting of veteran leader Zine Al Abidine Bin Ali, but has been struggling to restore security and stability.

A policeman was killed in clashes with suspected Islamist fighters near the border with Algeria on Monday, stoking fears of a spread of militancy in the north African nation.

The union had accused supporters of the ruling party of being behind last week’s clashes in Tunis in which at least 250 people were injured after the UGTT called for protests to demand jobs, investment and the sacking of an Ennahda governor.

But Ennahda chief Rached Ghannouchi condemned the violence and said some UGTT leaders wanted to overthrow the government.

The government on Saturday temporarily removed the local governor, promised jobs to victims of the 2010 uprising, and police stopped using birdshot after UN criticism.

Tunisia is preparing to mark on December 17 the second anniversary of a street peddler’s self-immolation that led to a revolution and the “Arab Spring” — uprisings in Egypt, Libya, Yemen, Syria and Bahrain.

The revolution toppled Bin Ali, whose police state had repressed Islamists and promoted secularism.