Eggs and tomatoes flew at Planning Commission deputy chairman Montek Singh Ahluwalia as he arrived at Presidency College for a seminar on Saturday.
The missiles, thrown by students protesting the failure of the government to control prices, missed the target and hit college principal Amitabha Chatterjee instead.
The attack caught the security personnel off guard. Ahluwalia was hurriedly escorted inside for the seminar in the economics department.
The demonstration was organised by members of the CPM-backed Students' Federation of India supporters and Maoist-backed United Students' Democratic Front.
Nisar Ahmed, officer in charge of Jorasanko police station, denied that the unions had thrown eggs and tomatoes.
"I was escorting him till the seminar hall. No such incident occurred. They were only showing him black flags and shouting slogans," he said.
Ahluwalia did not seem too perturbed.
"They are students and they have every right to protest," he told PTI.
At the seminar, Ahluwalia criticised the Bengal government for poor economic growth. He held the slow bureaucracy responsible.
He also pointed to corruption in sectors like agriculture and health.
Ahluwalia said the present food price hike was due to diversification of agriculture from foodgrain farming to alternative farming like horticulture, medicinal plants and commercial farming.