LAHORE - The Punjab Professors and Lecturers Association (PPLA) announced on Sunday that teachers would observe strike in colleges after 10am across Punjab as the government remained unmoved by protests by college lecturers, professors and assistant professors. Hundreds of teachers under the banner of PPLA have been staging a sit-in in front of the Punjab Assembly for the last six days and demanding increase in pay scale and promotions on time but no significant progress has been made on their demands.  PPLA was formed in 1996 and now the association is an elected representative body of 22,623 college teachers in around 640 colleges of Punjab.