This is Amnesty International's report:
On 12 June, five members of the ‘Abdelqader family were killed in another bombardment which destroyed four adjacent houses in the Old City in Sana’a. The strike would have likely caused many more casualties had many of the neighbours not left the area after a powerful airstrike targeted the nearby Defence Ministry compound (200 metres to the south) two days earlier.
The Saudi Arabia-led coalition spokesman Brigadier-General Ahmed al-‘Assiri denied responsibility for the strike but a fragment of the bomb recovered from the rubble of the houses shows that it comes from a 2,000 lb (900 kg) bomb, the same type which has been widely used by the coalition in various parts of Yemen.
The Old City, Sana’a (Sana’a governorate), 12 June 2015
A coalition strike in the Old City of Sana’a destroyed four adjacent houses on 12 June at 2AM killing the five members of the Abdelqader family who were inside: Hassan Yahya Abdelqader, his wife Ummat al-Malik, his brother Rashad and son Abdullah and his cousin Shawqi. Hassan’s brother, Mohamed, who lives nearby, told Amnesty International:
“We heard a plane flying over us at around 1:50AM. So my family and I hid under the staircase, the safest place in the house. At 2AM we heard an explosion. A few minutes later Shawqi’s mother called me and asked me to go to check on him. He had called her from under the rubble asking for help ... I ran over there. With the neighbours we started to dig through the rubble with our hands. Shawqi was dead when he was pulled out of the rubble at 5AM. He was married with five-year-old twins and his wife is six months pregnant. Thirteen people live in the houses, most of them women and children, but they had left two days earlier, after another airstrike hit the Defence Military Compound [200 metres to the south].”
another photo of Old Sanaa on 12 June #مليون_صوره_من_الجرائم_السعوديه_في_اليمن #Saudi_Destroy_Yemen pic.twitter.com/YiWfHoBFIx— Pray 4 Yemen ❤ (@fa_ansi) October 1, 2015
Before & after pics of KSA airstrikes on Old City Sana'a #Yemen UNESCO Heritage site via @alexkpotter @hamedalbukhiti pic.twitter.com/IoGMqWZs7N— Hisham Al-Omeisy (@omeisy) June 12, 2015
This is Mwatana's report of the incident (listed as 13 June but other sources including Tweets at the time state this happened early morning on 12th June):