Who shot a Secret Service officer at the Trump press dinner?

Nearly a week after a suspect allegedly tried to assassinate President Donald Trump at a press gala, key details about the shooting remain unclear.

As the investigation has evolved, prosecutors' statements have changed on whether the suspect shot a US Secret Service officer as gunfire rang out at the Washington Hilton last Saturday.

The president and other top officials have said a Secret Service officer was shot as the attacker charged a security checkpoint at the hotel, and that he survived thanks to a bulletproof vest.

But court documents filed by government attorneys do not explicitly allege the accused shot an officer on the night of the White House Correspondents' Association dinner.

The Secret Service officer also fired five times on the suspect as he charged, authorities said, but did not strike him.

"There's this insatiable public interest in the case, pressure to get information out to the public," Mark Lesko, a former US Attorney for the Eastern District of New York, told the BBC.

"But on the other hand, you want to conduct a thorough investigation, which could take weeks in a case like this."

It was understandable that law enforcement could make contradictory public statements in the heat of such a high-profile investigation, Lesko said.

But any inaccuracies could open the door for defence attorneys to poke holes in the case, he warned.

The BBC has contacted the justice department for comment.

The Secret Service and US Attorney's office for the District of Columbia declined to comment.

The public first learned from Trump that a Secret Service Officer had been shot.

He told reporters at a Saturday news conference that the agent "was shot from very close distance with a very powerful gun".

An affidavit issued by the justice department that night named Cole Tomas Allen, 31, as the suspect, and listed the charges against him, including that he discharged a firearm.

Allen, who is in custody, was armed with a semi-automatic handgun, a pump-action shotgun and three knives, according to authorities.

On Sunday, Acting US Attorney General Todd Blanche was asked on CBS News if the alleged assailant had shot the Secret Service agent.

"That's what we understand as of now," Blanche replied.

But at a news conference on Monday, he retreated from that stance. A reporter asked him again who had shot the officer.

"We wanna get that right, so we're still looking at that," Blanche said.

It appeared, he said, that five shots in total were fired during the incident.

Blanche said the suspect "fired out of a shotgun, and we know that happened".

He added that the ballistics were still being "looked at and finalised".

The same day, the government unveiled its criminal complaint against Allen.