Greece installed two electronic devices that can produce strong sound waves that cause deafness in the area bordering Turkey to prevent possible refugee waves entering the country.
Two Long Range Acoustic Device (LRAD) that can also cause severe pain and serious health problems to those who are exposed to it were delivered to police responsible for the border, according to media reports.
Four drones, 15 thermal cameras, five Zodiacs boats and 10 armored patrol vehicles (APV) were also integrated into the border surveillance system.
Greece also began building a new fence across its northeastern border with Turkey.
The fence will be 27 kilometers (17 miles) long and eight elevated observatories will be constructed to be used by the army.