The United States has found no direct link between the Russian government and the downing of Malaysia Airlines Flight 17 last week, three senior intelligence officials said Tuesday.

The officials repeated their belief that pro-Russian separatists fired the missile that took out the jetliner over Ukraine, killing 298 people, but they said they could not say definitively that the separatists did it.

“There’s not going to be a Perry Mason moment,” one U.S. official said. “We don’t know who pulled the trigger.” The White House stressed that it was not backing off what President Barack Obama, Secretary of State John Kerry and U.N. Ambassador Samantha Power have said for days — that Russia provided training and support for the separatists who probably shot down the plane, and therefore bore some responsibility.

Instead, the intelligence officials were “just saying that we don’t know if Russians pulled the trigger,” one administration official said

- The European Union threatened Russia on Tuesday with harsher sanctions over Ukraine that could inflict wider damage on its economy following the downing of a Malaysian airliner, but it delayed action for a few days.

Efforts to forge a united front were hampered by a French announcement that the planned delivery of a warship to Moscow would go ahead despite U.S. and British pleas to halt it.

5. On the day of the crash Kiev intensified Kupol-M1 9S18 radar activity, key BUK system components. Why?

“Also, July 17 saw increased activity on the part of Ukraine’s Kupol-M1 9S18 radars, which are part of the Buk system. Here on this chart you see that there were seven radars operating on July 15, eight radars operating on July 16, and nine radars operating on July 17 in the area. Then, starting with July 18, the intensity of radar activities radically decreased, and now there are no more than two or three radars operating a day. The reason behind this is yet to be found.”

6. What was a military plane doing on the route intended for civilian flights?

“There were three civilian planes in the area performing their regular flights at this time. There was a flight from Copenhagen to Singapore at 17:17, there was a flight from Paris to Taipei at 17:24, and then there was the flight from Amsterdam to Kuala Lumpur.”

“Also, Russian monitoring systems registered that there was a Ukrainian Air Force jet, probably Su-25, climbing and approaching the Malaysian Boeing.”

“The Su-25 was 3-5 km away from the Malaysian plane. Su-25 is capable of climbing to the altitude of 10,000 meters for a short period of time. Its standard armament includes R60 air-to-air missiles, which are capable of locking and hitting targets from 12 km and which are guaranteed to hit the target from the distance of 5 km.”

8. Where did the launcher – from the video circulated by Western media and showing a Buk system being moved allegedly from Ukraine to Russia – come from? As the video was made on the territory controlled by Kiev, where was the launcher being transported?

“I’d like to say that the information we have presented here is based on objective and reliable data from various technical systems – unlike the groundless accusations made against Russia,” said Kartopolov.

“For example, media circulated a video supposedly showing a Buk system being moved from Ukraine to Russia. This is clearly a fabrication. This video was made in the town of Krasnoarmeisk, as evidenced by the billboard you see in the background, advertising a car dealership at 34 Dnepropetrovsk Street. Krasnoarmeysk has been controlled by the Ukrainian military since May 11.”

9. Where is it right now? Why are some of the missiles missing on the launcher? When was the last time a missile was launched from it?