§134-8 Ownership, etc., of automatic firearms, silencers, etc., prohibited; penalties.
...
(c) The manufacture, possession, sale, barter, trade, gift, transfer, or acquisition of detachable ammunition magazines
with a capacity in excess of ten rounds which are designed for or capable of use with a pistol is prohibited.
This subsection shall not apply to magazines originally designed to accept more than ten rounds of ammunition
which have been modified to accept no more than ten rounds and which are not capable of being readily restored
to a capacity of more than ten rounds.
...
(d) Any person violating subsection (a) or (b) shall be guilty of a class C felony and shall be imprisoned for a term of five years without probation.
Any person violating subsection (c) shall be guilty of a misdemeanor
except when a detachable magazine prohibited under this section is possessed while inserted into a pistol in which case the person shall be guilty of a class C felony.
[L 1988, c 275, pt of §2; am L 1989, c 261, §6 and c 263, §4; am L 1992, c 286, §§3, 4]
You should probably take them to a licensed gun dealer and have them help you with either blocking them or exchanging them.
That's what I would do anyway.