Whoever harbours, receives or assembles in any house or premises in his occupation or charge, or under his control, any persons, knowing that such persons have been hired, engaged or employed, or are about to be hired, engaged or employed, to join or become members of an unlawful assembly, with the intention of permitting or facilitating them to join or become members of an unlawful assembly, or of screening them or any of them from punishment, shall be punished with imprisonment for a term which may extend to 2 years, or with fine, or with both.