In anticipation of being intercepted, Ben had recorded a video message, which was released earlier.
In the video, he said: “Tell my government to end complicity with Israel and to bring me home. Stop the genocide.”
Trowell said her son has long been a supporter of Palestine, who “became more and more involved and outraged at the injustice of the situation”.
“He said he really believed he was going to make it this time to Palestine to help the Gazans and deliver them aid.
“God, I want him home, I want him safe and sound,” she said.
“I think what they’ve done is an illegal act. It’s much bolder than what they did last time, they’ve come 600 miles from their country to do this in international waters.
“I’m waiting for our government to be speaking out against it,” she added.
The Israeli foreign ministry said that “due to the large numbers of vessels participating in the flotilla and the risk of escalation, and the need to prevent the breach of a lawful blockade, an early action was required”.
An FCDO spokesperson said: “We’re closely engaging with Israeli authorities with the expectation that the situation will be resolved safely and in line with international law.
“Efforts to deliver aid by sea highlight the dire humanitarian situation in Gaza.
“Israel must do more to allow sufficient aid into Gaza, in line with agreed minimum targets.”
