The following is a timeline of the Syrian Civil War from May to August 2016. Information about aggregated casualty counts is found at Casualties of the Syrian Civil War.
May 2016
12 May
Mustafa Badreddine, a senior Hezbollah is killed by suspected artillery bombardment by an armed Sunni group at Damascus International Airport. Opposition fighters, consisting of Ahrar al-Sham and the al Qaeda-affiliated Nusra Front capture the Syrian Alawite village of al-Zara and dozens of Alawite civilians are kidnapped.
14 May
Militants of the Abu Amarah Battalion fired a rocket at the Radio and TV Center in Aleppo, Syria. The attack left four journalists wounded.
23 May
Reuters reports nearly 150 people are killed and at least 200 wounded in a series of car bomb and suicide attacks in the Syrian cities of Jableh and Tartus in government-controlled territory that hosts Russian military bases. The Islamic State of Iraq and the Levant group claims responsibility.
24 May
New satellite imagery from Stratfor appears to reveal the destruction of four Russian attack helicopters and 20 lorries at the Tiyas military airbase after a reported attack which was conducted last week by the ISIL. U.S. backed Syrian Democratic Forces, led by Kurdish forces, launch an operation to capture Raqqa, the de facto capital of Islamic State of Iraq and Syria. One week later the offensive stalls. Nusra Front rebels have captured the town of Deir Khabiyeh, south of Damascus.
27 May
ISIS captures Kafr Kalbeen and Kaljibrin villages from rebel forces in northern Aleppo, cutting the supply lines toward the rebel stronghold of Mare.
30 May
Russian aircraft conducts eight air strikes targeting the Syrian National Hospital in Idlib city left at least 50 dead with another 250 injured. As many as 17 of the 50 killed are believed to be children.
31 May
Syrian Democratic Forces seizes 11 villages and farms from the Islamic State in northern countryside of Raqqa. Meanwhile, a pro-government source announces SAA advancing towards Al-Raqqa City in race to capture it. Syrian government aircraft conducts heavy raids on residential areas for months in Idlib, killing more than 30 people and injuring dozens.
June 2016
3 June
Syrian government bombing raids in and around Aleppo city kill 31 civilians, including 10 when their bus was hit.
4 June
Russian Foreign Ministry says that the United States asked the Russia not to carry airstrikes on al-Qaeda linked Nusra Front to avoid "moderate opposition" being hit.
5 June
Syrian government air strikes hit the Qaterji neighborhood in Aleppo killed nine civilians, and two others, including a child, were killed in the Mayssar neighborhood of the city. Another five civilians are killed in two other districts and on the city’s outskirts. Syrian government and Russian jets bomb the rebel-held Idlib, setting fire to a bustling market in the heart of the city, injuring more than 30 people, and killing at least three.
8 June
Regime air strikes on the UN's children's agency UNICEF and doctors at Al-Hakim children's hospital, the nearby Al-Bayan hospital away and the Abdulhadi Fares Clinic, in the rebel-controlled part of Aleppo city spark a desperate bid by medical staff to rescue at least nine newborns and kill 15 people.
9 June
The besieged rebel-held Darayya town receives its first United Nations food delivery since 2012. Shortly afterwards, Assad forces bombard the town, dropping indiscriminate barrel bombs from helicopters as residents shared food. The United States condemns Assad regime, accusing it of bombing starving civilians just hours after they received a long-delayed UN aid shipment. France also voices outrage, accusing Damascus of "extraordinary duplicity”, saying the regime had finally granted access for aid after heavy international pressure “and then the bombing restarted."
10 June
A friendly fire incident in late May in which American aircraft bombed by error a U.S raised rebel group ("Mustafa Sejry") is acknowledged by U.S Central Command. According to an official, 4 anti-ISIL personnel were killed by error, whilst other sources claim 10 were killed.