31.   Its timing device had failed to operate.

32.   It had been delayed because some devices failed to give a warning during tests.

33.   Otherwise the device could fail to explode, or even detonate prematurely.

34.   The airport was the site of a failed bombing last June in which the device failed to detonate properly.

35.   The device failed to go off Wednesday night because army disposal experts disarmed it first.

36.   The device failed to go off.

37.   The Liberation Tigers of Tamil Eelam tried to bomb Colombo international airport in June but the explosive device failed to go off properly.