Armed officers joined those from the counter terrorism command when the arrests were made at about 4am.
Police say the operation was not linked to the Olympics.
A 38-year-old woman was also arrested for alleged fraud offences and two other men were held over alleged immigration offences.
More top news
Whilst the weather may be a lot quieter here in the UK, it's a very different story for the the Mediterranean this weekend.
The RSPCA has outlined in detail its policy on the shooting of seals that attack salmon stocks "as an absolute last resort".
We started the week warm, wet and windy but it will end much cooler and brighter.