FOUR government troops were killed as government troops carried out over 100 attacks on eastern Ukrainian rebel positions today, a Kiev official said.

Fighting in eastern Ukraine has increased since President Petro Poroshenko turned his back on a 10-day ceasefire in preference for a military solution. 

Defence official Andriy Lysenko said that three troops had died in rebel attacks on government vehicles and checkpoints, with another 10 wounded. 

And federal border guards reported one guardsman killed when the Novoazovsk crossing point came under attack by mortars in the Donetsk region.

Officials said that pro-Russian rebels had been forced out of three villages.

Border posts have become a key issue, since Ukraine claims that military equipment and reinforcements are flowing across the border from Russia, which Moscow denies.

Kiev claimed to have recaptured a key border post on Tuesday at Dovzhanskiy. Rebels had trapped it with explosives.

Another one of the main crossings, at Izvaryne, was closed yesterday because of fighting.

Ukrainian officials said that rebels had shelled troops in the area and a government armoured vehicle was destroyed by a mine near the crossing.

Fighting was also under way in Lugansk, the other eastern region where separatists have declared independence. 

A government air-launched missile hit a school near a rebel position. The attack happened overnight and no injuries were reported.

German Chancellor Angela Merkel said today in Berlin that she “cannot rule out that we will have to go further” in imposing sanctions on Russia.