Late on Wednesday morning, two warplanes flying at high altitude fired missiles into the rebel-held town of Talbiseh in western Syria, killing at least 20 civilians and injuring dozens more, according to an opposition activist who witnessed the attack.
Adnan, who is also a school teacher, says he knew this was something different when he saw how high the aircraft were flying and then went to see the destruction caused by the explosions.
"It was very frightening, the attack was so powerful and the casualties were so many," he says.
He is convinced these were Russian air strikes and while it's not possible to independently verify his account, it does tally with other reports.
Videos apparently from the town show collapsed buildings and people desperately pulling the dead and injured from the rubble.
Talbiseh - which lies on a vital road running from the capital Damascus to the northern city of Aleppo - has been in rebel hands since 2012.
The rebels are mostly locals, and Adnan says they are affiliated to the Free Syrian Army.
The jihadist group Ahrar al-Sham is also known to have a presence in the town, but it is a bitter enemy of Islamic State and a powerful force fighting to bring down Syrian President Bashar al-Assad and his regime.
"They (the Russians) attacked us because we are against the regime," says Adnan, "now everyone is afraid of the warplanes and afraid of more attacks."
Many of those who died in Wednesday's air strikes were inside the post office building which is being used to distribute bread to the population, activists say.
According to Adnan, the field hospital - which already lacked medicine and blood supplies - was overwhelmed by the number of casualties.
And now the people of Talbiseh await the next attack, either from Russian planes or the Syrian army.
The rumour in Talbiseh is that the air strikes could be a prelude to a new ground offensive by Syrian troops with the aim of finally regaining control of the rebel town and the strategic highway running north to Hama and Aleppo.