AMNA NAWAZ: Britain expects 3,000 to 4,000 unaccompanied children to cross the English Channel in small boats this year.

The government's trying to devise a way to keep these young asylum seekers safe after the abduction of 200 unaccompanied minors while supposedly under the state's care.

From Brighton, special correspondent Malcolm Brabant reports.

MALCOLM BRABANT: The remains of Brighton's West Pier and the return of migratory birds are a metaphor for Britain's broken asylum system, shamed by the abduction of scores of unaccompanied minors by ruthless criminal gangs.

Brighton is one of Britain's sanctuary cities, where refugees and economic migrants are welcomed and supposed to feel secure.

Yet this quiet residential street was anything but safe for 76 unaccompanied minors temporarily housed in this hotel.

It's feared they're now drug runners or sex slaves.

HANNAH ALLBROOKE, Deputy Leader, Brighton and Hove City Council: It's a massive scandal, and I think the government are not taking it seriously, and they never have.

MALCOLM BRABANT: Besides being deputy leader of the City Council, Hannah Allbrooke chairs a committee overseeing children's interests.

The government relies on local authorities to care for unaccompanied minors, who are often rescued at sea by lifeboats and brought ashore while their asylum claims are assessed.

But Allbrooke says the minors were under state protection when they disappeared.

HANNAH ALLBROOKE: What's happened was predicted and predictable.

They have had children going missing.

And that's really, really sad and really shocking.

On top of that, we have had reports of really bad bullying behavior in the hotels and that children have been treated very badly.

And this is all part of the government's hostile environment plan, where refugees and asylum seekers in this country are treated so badly.

MALCOLM BRABANT: Traffickers charge asylum seekers up to $7,000 for crossing the channel.

Those who can't afford it are sometimes required to pay off the debt by working in the drugs trade.

The government has a moral and legal obligation to protect unaccompanied minors.

And, by keeping them safe, what they would also be doing is disrupting the smugglers' business model.

On a handful of occasions, police have prevented young people from being taken away.

But by abducting so many with virtual impunity, gangs are proving that their type of crime pays dividends.

On the defensive in Parliament, Immigration Minister Robert Jenrick: ROBERT JENRICK, U.K. Minister for Immigration: The rise in small boat crossings has placed a severe strain on the asylum accommodation system.

We have had no alternative but to temporarily use specialist hotels to give some unaccompanied minors a roof over their heads, whilst local authority accommodation is found.

We take our safeguarding responsibilities extremely seriously.

MALCOLM BRABANT: Brighton lawmaker Caroline Lucas.

CAROLINE LUCAS, U.K. Parliament Member: This is horrific.

Mr. Speaker.

Vulnerable children are being dumped by the Home Office.

Scores of them are going missing.

And I can tell the minister there is nothing specialist about these hotels.

We are not asking him to detain children.

We are asking the Home Office to apply some basic safeguarding, so we can keep them safe.

PETER KYLE, U.K. Parliament Member: The uncomfortable truth for us is if one child who is related to one of us in this room went missing, the world would stop.

MALCOLM BRABANT: The hotel is in Peter Kyle's constituency.

PETER KYLE: In the community I represent, a child has gone missing.

Then five went missing.

Then a dozen went missing.

Then 50 went missing.

And, currently, today, 76 are missing, and nothing is happening.

MALCOLM BRABANT: The government is under pressure to stop using hotels as temporary accommodation for asylum seekers.

HANNAH ALLBROOKE: The wider picture is that, when a refugee child arrives in this country, they should be taken into care by council.

But council is really struggling to find the places to put these children.

So, therefore, the government are commissioning these hotels, almost out of the total chaos, whereby they don't have anywhere else to go.

MALCOLM BRABANT: Criticism isn't just coming from the left.

NIGEL FARAGE, Former Brexit Party Leader: There are 140,000 people who've entered this country and are claiming asylum that haven't yet been processed.

MALCOLM BRABANT: Prominent anti-immigration activist Nigel Farage leads the charge from the right.

NIGEL FARAGE: And they have run out of inner-city hotels to put them in.

They have tried former army camps.

But those conditions there simply aren't good enough.

No, what was good enough for national servicemen or serving British soldiers not good enough for the young man crossing the English Channel.

MALCOLM BRABANT: Uncomfortable questions for Prime Minister Rishi Sunak.

TULIP SIDDIQ, U.K. Parliament Member: Ministers have admitted that they have no idea about the whereabouts of these children.

So, could I ask the prime minister, does he still think that the U.K. is a safe haven for vulnerable children?

RISHI SUNAK, British Prime Minister: Mr. Speaker, the United Kingdom has opened up its hearts and homes to hundreds of thousands of people over the last few years from Syria, from Afghanistan, from Ukraine, from Hong Kong, and provided refuge and sanctuary to many children in that process.

But the reports that we have read about are concerning.

MALCOLM BRABANT: Many of those missing from the street are Albanian and aged over 16.

Brighton Council's Hannah Allbrooke: HANNAH ALLBROOKE: There are certain nationalities that we know, when they arrive in this country, whether they're in local authority care or whether in a hotel, they are at risk of trafficking.

Albanian children's one of them.

Vietnamese children is one of them as well.

And these are some of the nationalities that we have seen missing.

So there's potential modern slavery implications, as well as just, where have they gone?

MALCOLM BRABANT: Britain regards Albania as a safe country, and Prime Minister Sunak believes its citizens should be barred from claiming asylum.

This is his new strategy.

RISHI SUNAK: So, I have worked with the Albanians to put in place a new deal, which means, for people coming from Albania illegally, we will be able to remove them safely back to Albania.

And that is already happening.

We're putting illegal migrants from Albania back on flights, and that will ratchet up over the year.

And that's tangible improvement in the situation.

MALCOLM BRABANT: Successive British governments have talked tough, but people keep crossing the channel, just like the migratory birds.

Some experts predict 2023 could see 100,000 landings, twice as many as last year, even though the price of a ticket can be enslavement.

For the "PBS NewsHour," I'm Malcolm Brabant in Brighton.