"As far as I know, there was a breakdown and this is why it happened. It's a certain one-time breakdown, as far as I know," Pangonis told LNK Zinios (LNK News) on Tuesday.
His comments came after Klaipeda prosecutors launched in investigation into pollution in Lithuania's seaport. Grigeo Klaipeda, Grigeo's subsidiary operating in Klaipeda, is suspected to have caused it.
Prosecutors say the damage done to nature could be valued at "tens of millions" of euros.
The Nasdaq Vilnius Stock Exchange on Tuesday suspected trading in Grigeo shares.