On Monday, news broke that Carlos Gregorio Vasquez, a 16-year-old Guatemalan boy died while in government custody. Since December, five Guatemalan children have died after crossing the US border. As activists worry that this issue is swept under the rug and immigration agencies try to downplay their role, at least one presidential candidate has been vocal about the need to hold the governmental agency accountable. In a series of tweets, Castro spoke about the deaths happening in government custody.

“While Donald Trump fear-mongers and demonizes immigrants every day, children are dying in government custody under his watch. His agenda has failed. It’s time for a new moral leadership and a compassionate approach to immigration that values all human life,” he tweeted.

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In a second tweet, he further elaborated why what’s happening is so concerning. “Five children have died in United States custody in LESS [THAN] SIX MONTHS. This is an outrage. And it is the legacy of the Trump [Administration] – they don’t care about this human life. Accountability NOW.”

Not all of the candidates have had something to say on this latest development, and this is likely due to the fact that Castro has made immigration a central part of his presidential bid. While other candidates might mention immigration on their websites, none of them – except Castro – has a comprehensive immigration plan.

In April, Castro introduced his plan, which seeks to end immigrant detention, provide a pathway to citizenship for undocumented immigrants, strengthen family reunification, and more.