Police in Tanzania have confirmed the arrest of three Tanzanian nationals by Kenyan security forces in connection with terror attacks.

The suspects, believed to have been involved in a string of deadly attacks in the coastal towns of Lamu and Mombasa, were arrested by the Kenya Defence Forces. Unconfirmed reports put the number of Tanzanians who had been arrested at six.

Tanzania's Director of Criminal Investigation (DCI), Mr Issaya Mngulu, confirmed to The Citizen that the suspects were being interrogated and were due to appear in court to be charged with illegal stay.

Police in Tanzania were yet to confirm if the suspects were associated with terrorism, adding that they were still communicating with their Kenyan counterparts. Kenyan media reported on Monday that the Tanzanians were arrested in Lamu over the weekend. They were immediately flown to Nairobi in a KDF helicopter under tight security.

Siraji Ramadhan and another suspect who was identified only as Swaleh , both 26 years old, had boarded a Tahmeed bus destined for Mombasa when they were arrested. The Citizen could not immediately establish the name of the third suspect.

“They were arrested in a bus that operates between Tanzania and Mombasa. We are following up the matter to see if the said Tanzanian nationals have any links with terrorism,’’ said Mr Mngulu.

According to media reports, Kenyan military personnel recovered two expired Tanzanian passports from the suspects, who had earlier on Sunday transported their luggage to Mombasa by another bus.

Forensic investigations conducted by detectives on their mobile phone data showed that the two are “well connected with Al-Shabaab and communicate frequently with other people in foreign countries”.

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The media quoted Tana Delta police boss Robison Thuku confirming the arrests and said the suspects would be further questioned in Nairobi. “These are the elements we have been looking for and others will also be arrested,” he told Kenya’s Star newspaper on the phone.

This is not the first time people said to be Tanzanians have been arrested in Kenya over terrorism. In October last year, the Kenyan military arrested three Tanzanians inside Somalia on suspicion they were on their way to join Al-Shabaab.

Police said the suspects were from Dar es Salaam, and had travelled to the Tanzania-Kenya border at Lungalunga, then drove to Mombasa, Malindi and Lamu before crossing into Somalia. According to police, the three were headed to Kismayu to join “the holy war” that is allegedly being led by Al-Shabaab.

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Terrorist attacks have in recent months caused panic and fear in both Kenya and Tanzania, especially in Arusha, Zanzibar and along the Kenyan coast.

Last week, six people were charged with terrorism in Arusha. The accused allegedly carried out the bomb attack at a popular restaurant in the city earlier this month. They were among eight people who were arrested last week during an operation in which seven hand grenades and bomb making material were also seized by law enforcers.

Lamu county along the Kenyan coast has also been continuously plagued by acts of terrorism with Al Shabaab claiming responsibility. However, Kenya's president Uhuru Kenyatta has blamed the attacks on local political networks.