Kerry spokesman Glen Johnson said police found a pellet gun in the man's vehicle and arrested him Sunday for possession of an open container of alcohol, The Boston Globe reported.
Kerry was visiting his wife, Teresa Heinz Kerry, at Spaulding Rehabilitation Hospital when State Department security personnel observed the man taking pictures of Kerry's home and called police, Johnson said.
Kerry's wife suffered a seizure earlier in July at Nantucket and was in critical condition when she was flown to Massachusetts General Hospital. After her condition improved, she was transferred to Spaulding.
Notable deaths of 2014 [PHOTOS]