Al-Shabaab, the militant group which has claimed responsibility for the Nairobi shopping mall attack, tells Channel 4 News "if Kenyans don't leave our land, we will wage a real war."

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Armed militants from al-Shabaab, the Somali-based, al-Qaeda-linked group, are still inside the Westgate shopping centre in Kenya's capital Nairobi. Reporter Jamal Osman interviewed a spokesman for the group to find out the reasons for the attack, and what message they have for the West.

Jamal Osman: "Why did you do the attack?"

Al-Shabaab spokesman: "The reason we attacked is to defend our people our country, because Kenya attacked us, they are still controlling parts of our land.

"We have been peaceful neighbours, but they are the ones who attacked us and we are defending ourselves. Whether you are Muslim or Christian, the law says you have to defend yourself from those who attack you.

JO: "You have killed lots of different nationalities, including Britons; don't you fear powerful countries will come after you?"

AS: "We have told the Kenyans and those who come to Kenya that we will not tolerate what Kenya is doing to us. We told them we would defend ourselves and we warned them about travelling to Kenya.

"Kenyans have blood on their hands. Anyone who is prepared to come to Kenya must be prepared to face the reality, and we don't fear Europeans and Americans because we are not weak.

"And we are saying to the Europeans and the Americans who have been supporting those who have been attacking us, you should tell the Kenyans to stop their aggression if you want to be safe."

At least 59 people, including three British nationals, have been killed in the Nairobi Westgate shopping mall attack (picture: Reuters)

JO: "Why did you target Westgate mall?"

AS: The reason why we have targeted the Westgate mall is because the Kenyans and their government have taken up arms against us, they are our enemies.

"They have sent their men into Somalia; they have supported their government to invade our country.

"For us anywhere in Kenya is the same, we will hit them wherever we can. The reason we targeted Westgate is that we know it's a place where they feel the most pain.

"It's because it brings in a lot of money and is in the centre of the city. It's where they will feel pain and because we wanted to send a message and we didn't want to waste our message.

"We wanted our message to reach every Kenyan."

JO: "Are your fighters inside the mall still fighting?"

AS: "It's been more than 27 hours; they are still inside and still in control."

JO: "I am hearing there is a female fighter in there too?"

AS: "We don't send our women onto the battlefield. I am saying to you we do not use women on the battlefield."

JO: "What are you expecting to happen now, what will be the outcome of this?"

AS: "God willing, we are expecting the Kenyans to get the message that if you spill blood, your blood too will be spilt. For them to know that they cannot be in control of Kismayu, Dhobley and Afmadow and expect to live peacefully in Nairobi. That's the message we want to send to them.

Security forces are inside the Westgate shopping centre, and are said to have militants 'pinned down' (picture: Reuters)

JO. "In some of your messages on Twitter you say this is just the beginning and you will keep going, or have you achieved your aims?"

AS: "We are saying to the Kenyans, leave our country. That's the first message. And if they refuse to leave our country then we will wage real war."

JO: "So your condition to the Kenyans, is leave your country if they want peace?"

AS: "If Kenyans want peace, they have to leave our country."

JO: "Why are you targeting innocent people?"

AS: "The foreigners have to leave the country because we (the Kenyans and al-Shabaab) are in conflict with each other and we are telling everyone not to be mistaken - Kenya is a war zone."

JO: "Since you say foreigners and British people have huge interest in Kenya, what's your message to them?"

AS: "We are saying to the British, since we believe they are helping the Kenyans, and Kenyans are their slaves, they (the British) should tell the Kenyans, they should order back the Kenyan army out of Somalia."

"And the English know Somalis will not give up the fight. We denied the British before, who are much stronger than the Kenyans."