Police in Northern Ireland said they arrested three men in relation to the "attempted murder" of a police officer in Omagh, about 60 miles (nearly 100 kilometers) west of Belfast.
The senior officer is in a critical but stable condition, officials said on Thursday.
Police said the arrests were made under the Terrorism Act.
Mark McEwan, an assistant chief constable, told the BBC that the main focus of the investigation is "violent dissident republicans, and within that there is a primary focus as well on New IRA." The splinter group of the Irish Republican Army (IRA) had claimed responsibility for two attacks in recent years.
Who was shot?
Officials identified the wounded officer as Detective Chief Inspector John Caldwell. The well-known senior officer has led investigations into murder, as well as organized crime and dissident paramilitary groups.
"John is a highly respected senior investigating officer who dedicates himself to service both in supporting victims and families in bringing others to justice," McEwan said in a statement.
What do we know about the shooting?
According to the police statement, two gunmen attacked Caldwell on Wednesday evening at around 8 p.m. local time outside a youth sports center, where he had been coaching an under-15 soccer team.
Caldwell was putting footballs in his car when two gunmen opened fire, police said. His young son was with him when the shooting happened.
"That shows the absolute callous nature of this attack, and it is utterly disgusting that the gunmen carried out this attempted murder in front of crowds of adults and children," McEwan said.
"The gunmen fired from close range in the busy sports training area, which could also quite easily have killed or seriously injured children who were present at the time of the shooting," he added.
fb/rt (AFP, AP, Reuters)