Attacks in Saudi Arabia: edit in The Express Tribune, July 6th, 2016.

Pessimistic analysts have long predicted the unraveling of Saudi Arabia, a colonial construct stitched together in the aftermath of the First World War. Oil was, and will remain, the principle reason for the support of its unlikely bedfellows internationally. However, these pessimistic analysts notwithstanding, that equation is not going to change. Saudi Arabia is not about to crumble in the near to medium term, but internal tensions are escalating. Despite being one of the most tightly controlled states in the world, with a massive security apparatus, suicide bombers were able to strike three times on July 4. They killed five and injured six and were targeting the American embassy (on US Independence Day), Shia worshippers and the security forces themselves. There appears to have been close coordination of the attacks as they were almost synchronous.
The numbers killed and injured were low but the attacks were highly symbolic. They took place during the holy month of Ramazan, very close to Eid and one of the targets was Medina, considered one of the most sacred places for Muslims all over the world. The bombers do not act alone. There are concentric circles of support that surround them. They need logistical support, there has to be a competent bomb-maker (it is almost never the bomber themselves) and they are going to need money, possibly quite a lot of it. Reconnaissance will have been conducted — and all of these factors are well within the understanding of Saudi Arabia’s security agencies that in this instance have had a serial failure to predict and prevent the attacks.
The diversity of targets must also be a matter of concern for the Saudi authorities, as it is perhaps indicative of groups that have differing goals working collaboratively. One of the bombers is identified as of Pakistan origin and living in-country for 12 years, the origins of the other two unknown. The origin of that one bomber will also be giving rise to concern given the millions of foreign workers that underpin the Saudi economy and the lifestyle of the indigenous population. There is an inbuilt instability in Saudi Arabia that only increases over time, no matter how controlling the regime may be, and bombers always seem to find a way through eventually.
http://tribune.com.pk/story/1137061/attacks-saudi-arabia/