THESSALONIKI, Greece,(AFP) - A disgruntled ex-employee gave himself up to Greek police after shooting and wounding his ex-boss and a worker and taking two others hostage Thursday, a police source said.

The injured men -- the company owner and another employee -- were taken to hospital. A company spokeswoman said their injuries were not life-threatening.

The gunman wounded the owner "in the neck, hand and side", said the Hellenic Environmental Systems Industry (Helesi) company in Komotini in northeast Greece.

The other employee, a Bulgarian, was hit in the legs.

The two hostages, company drivers aged 64 and 51, were held for 12 hours before emerging safe and sound, the police source said.

Helesi management said in a statement the 52-year-old hostage-taker, who had worked for the company since 2000, was dismissed "for an unstable, unfit and transgressive attitude".

Helesi -- which is based in Komotini, near the Greek-Turkish border -- recently dismissed around half of its 300 employees, the police said.

According to the head of a local union, Pantelis Mangalios, the hostage-taker was let go from a supervisory position.

"He was facing very serious financial problems," Mangalios said.

"Workers are beginning to have urges for revenge," he also warned, saying unemployment in this border region is at nearly 40 percent.

Greece is in the grip of a financial crisis and more than one million people are unemployed.

The Greek economy is not expected to limp back into growth before 2013.