21.   Authorities began looking at Karr and Waters.

22.   Acting on complaints by Plenel and other journalists, the authorities began an investigation of Prouteau.

23.   After the attacks, federal authorities began questioning hundreds of Middle Eastern, Asian and Muslim immigrants for possible leads or ties to terrorism.

24.   After the initial braking tests, the authority began doing exhaustive braking tests of all the car models, testing them under all conditions and speeds, he said.

25.   After the Utah bombing, the authorities began distributing the sketch of a hooded man wearing sunglasses who was thought to be the Unabomber.

26.   After The New York Times raised questions about the case, state health authorities did begin pressing for action against the company.

27.   But authorities began to worry that the group was going to change sides and support Pakistan.

28.   But it is appalling that Benjamin was still practicing years after health authorities began trying to revoke his license.

29.   By Tuesday, however, authorities began to emphasize the ways in which the inmate could still be surviving in the wild.

30.   By then, medical authorities had begun to reach some of the injured students, more people were evacuated and SWAT teams began a methodical search of the school.