PRISTINA : Four Kosovo opposition party activists, including a member of parliament, were jailed Friday for "terrorism" over a grenade attack on the parliament building last year.

Frasher Krasniqi, parliamentary deputy and spokesman for the main opposition party, the nationalist leftist Vetevendosje (Self-Determination) party, received the heaviest sentence, jailed for eight years. He denounced the court's decision as a "political affair" targetting himself and the other activists.

The Pristina court sentenced two other men to shorter jail terms while a woman who was given a two-year term was released.

No one was injured in the August 4, 2016 grenade attack , which caused only slight damage to the parliament.

The attack was followed by several others that rocked the capital ahead of a controversial vote on a border agreement with Montenegro.

The Self-Determination party firmly opposed the deal and its MPs repeatedly released tear gas in parliament in protest.

The agreement was negotiated with Montenegro by a previous government in 2015, but has still not been ratified.

It is crucial for Kosovo's bid to gain visa-free travel and for it to further integrate with the EU, which is a key goal for this tiny Balkan nation of 1.8 million people, which unilaterally proclaimed independence from Serbia in 2008.

In total six opposition party activists were arrested over the parliament attack. One was released, while the sixth, 26-year-old Astrit Dehari, died in custody.