The Battle of Piotrków Trybunalski was a battle in the Invasion of Poland which started with the German breakthrough during the Battle of Borowa Gora

Battle of Borowa Góra

Battle of Borowa Góra refers to the series of battles from 2nd to 5 September of 1939 that took place near the hills of Góry Borowskie, south west from Piotrków Trybunalski and east of Bełchatów....

. [1]

After the German breakthrough at Borowa Gora

Borowa Góra

Borowa Góra may refer to the following places:*Borowa Góra, Masovian Voivodeship *Borowa Góra, Subcarpathian Voivodeship *Borowa Góra, Świętokrzyskie Voivodeship...

, the Germans and their tanks and soldiers headed for the Polish town of Piotrków Trybunalski

Piotrków Trybunalski

Piotrków Trybunalski is a city in central Poland with 80,738 inhabitants . It is situated in the Łódź Voivodeship , and previously was the capital of Piotrków Voivodeship...

. German tanks attacked the town, but Polish 155 mm howitzers destroyed several tanks and the Germans fell back, returning again later that day. [2]

The Germans managed to destroy 7 Polish tanks with artillery, but just after, they lost five of their Panzer tanks. [2]
After receiving several more direct hits and losing two more large Panzer tanks, the German tank crews simply ran away. Polish 7TP

7TP

The 7TP was the Polish light tank of the Second World War. A development of the British Vickers 6-ton, it was significantly better armed than its most common opponents, the German Panzer I and Panzer II. A standard tank of the Polish Army during the Polish Defensive War of 1939, its production...

tanks pursued and kept beating the rest of the tanks off. The German soldiers now met the Polish infantry and attacked, but they were repelled by the Polish tanks. [2]

Soon, all the Germans retreated and by the end of September 6th, no hostile forces were in Piotrków Trybunalski.
Reference 2= http://forum.axishistory.com/viewtopic.php?f=55&t=147576

Reference 1= http://en.wikipedia.org/wiki/Battle_of_Borowa_G%C3%B3ra