The phrase "as the primary suspect" is correct and usable in written English.
It can be used in contexts related to investigations, crime, or any situation where someone is identified as the main person of interest or blame.
Example: "The police have identified him as the primary suspect in the robbery case."
Alternatives: "as the main suspect" or "as the chief suspect".
Keyworth emerged as the primary suspect.
Officials said the house fire was deliberately set, casting Mr. Stack as the primary suspect.
Now, as the primary suspect in last week's terror attacks on New York and Washington, he may well be hiding in the mountains outside Khost.
Others have expressed their opinions, in particular, about Osama bin Laden, whom the Bush administration has described as the primary suspect in the terrorist attack.
The man once seen as the primary suspect in the case was briefly released from prison last week before being rearrested.
Mr. Waagner's arrest was announced by Attorney General John Ashcroft, who singled him out last week as the primary suspect in the series of mailed warnings and packets of powdery substances.
But Brian M. Overstreet, the president of AdverseEvents, said, "The reality is that hundreds of thousands of cases are reported every year by front-line health care providers who purposefully identify a drug as being the primary suspect cause of a specific adverse event.
The Shin Bet, Israel's domestic security agency, has named Marwan Qawasmeh and Amer Abu Aisha, both residents of Hebron, as the primary suspects in the abductions.
Marwan Kawasme and Amer Abu Aysha, the two Hamas members identified by Israel as the primary suspects, have been missing since the teens first disappeared on June 12.
While he was in custody, McVeigh was identified as "John Doe No. 1," the primary suspect in the Oklahoma City bombing.
After Mr. Ramirez's arrest, Chief Beck maintained the he was the primary suspect, even as the search for accomplices continued.
