Staff Reporter :Intern doctors of different hospitals across the country on Sunday observed a three-hour work abstention demanding a rise in their allowances.They also gave a 15-day ultimatum to the government to press home for their demand.As part of the programme announced by Intern Doctors Association (IDA), interns of the capital organized a human chain followed by a rally in front of the Central Shaheed Minar and observed the work stoppage from 10am to 1pm.Intern doctors, said they would go for an indefinite strike if the government fails to increase their allowances to Tk 20,000 by next 15 days.