HARARE, Feb. 8 (Xinhua) -- The strike by some Zimbabwean public school teachers which started Tuesday continued to Friday despite a warning from the government to cut their salaries for time away from work.

A school headmaster in Glen View told Xinhua that teachers had stayed away from work Thursday and Friday in his area.

The government on Thursday warned the striking teachers that it would not pay them for hours spent away from work.

This follows threats by two teacher organizations that their members would intensify the strike starting Friday, citing government's failure to address their grievances over low salaries and other conditions of service.

Secretary for the Public Service Commission Vincent Hungwe said in a statement that the government would apply the "no work, no pay" rule.

The strike started at a low key Tuesday with a higher number of teachers reporting for duty.

However, it has since escalated with another school head in Macheke, Masholand East Province, saying that at his school about 40 percent of teachers had not reported for duty.

The two largest teachers' unions in the country, the Zimbabwe Teachers Association and the Progressive Teachers Union said in a joint statement Thursday that about 80 percent of their members had heeded the call to strike.

The two teacher unions have gone ahead with the strike while smaller teacher unions and the rest of the civil service have decided to seek further negotiations with the government.

A deputy school head in Highfield, also south-western Harare, said all teachers at the school had turned up for work, revealing the division among the teachers on the course of action to take.