According to the angle of inclination, it is very likely that the rocket has been launched from the south-west pic.twitter.com/aH2vZE9kCl
— Paul Gypteau (@paulgypteau) October 1, 2014
From The Interpreter (Ukraine Liveblog Day 227: Fighting Rages Around Donetsk Airport:
We geolocated the scene on Google Street View which is near the Sarepta Pharmacy and also showed the separatists' positions in the southwest. If OSCE is saying that the shelling is coming from the south, it is even less likely that the rockets were fired by the Ukrainian army at the airport.
The airport is where Ukrainian forces are. The way the shell landed shows that it could not have been fired from the airport, instead it was most likely fired AT the airport, but fell short, killing civilians instead.
There is supposed to be a ceasefire, yet the rebels/Russian army have not let up on trying to drive the Ukrainian army out of the airport at Donetsk. From the Interpreter's website, there are reports of the rebels firing at the airport from various domestic buildings and then moving on to other buildings, in effect putting civilians in harm's way. When civilians are hurt, the Russian Federation media blames the Ukrainian army for the deaths.
Though, specifically speaking, the ceasefire agreement is only between the Ukrainian army and the rebels, with the Russian Federation not included, because Russia's not invading - not officially anyway.