SAN JOSE, Calif. — A group of protesters attacked Donald Trump supporters who were leaving the candidate’s rally in San Jose on Thursday night. A dozen or more people were punched, at least one person was pelted with an egg and Trump hats grabbed from supporters were set on fire on the ground. There were no immediate reports of injuries or arrests, but police had declared the gathering an unlawful assembly about a half-hour after the rally ended. The crowd, which had numbered over 300 just after the rally, had thinned significantly but those that remained, filling about a city block near the San Jose Convention Center, were rowdy and angry. Some banged on the cars of Trump supporters as they left the rally and chased after those on foot to frighten them.