Seehofer has told Der Spiegel magazine that he is planning to submit a concept for enhanced covert checks and brief searches of travelers along Germany's border Switzerland.
He remarks followed Monday's death at Frankfurt's main railway station, where a Swiss-resident Eritrean migrant undergoing psychiatric treatment allegedly shoved a boy before a moving train. His mother survived being pushed.
"I will do everything possible to arrange intelligent controls at the border," Seehofer told Spiegel, referring to Germany's 347-kilometer (215-mile) boundary with the Swiss alpine republic.
Read more: boy dies after being pushed in front of train
The boy's death was seized upon by Germany's far-right to once more criticize what it regards as flawed migration and security policies under Chancellor Angela Merkel's coalition government since Europe's 2015 refugee crisis.
Seehofer told Der Spiegel that Germany as a whole had registered 43,000 unlawful arrivals in 2018.
Switzerland — like Germany — belongs to Europe's borderless Schengen Area, which includes 26 member countries and a total of 419 million residents. Authorities rely on roving checks by police and customs officials — on trains, highways and at airports.
Düsseldorf's Rheinische Post newspaper reported in January that federal police detected more than 14,000 unlawful entrants on long-distance buses and trains last year.
In sharp reactions, German opposition parties accused Seehofer of resorting to populist sentiment ahead of regional assembly elections in three eastern German states in September and October.
"Even with such controls, the suspected Frankfurt perpetrator would not have been stopped because there was no Europe-wide arrest warrant against him," said Benjamin Strasser, the interior affairs spokesman for the liberal Free Democrats.
Random and incident-prompted controls already take place along and inside Germany's borders, he added.
Won't improve security 'one jot'
"The populist announcement tactic of Horst Seehofer does not in any way make a contribution to the security of our country, and it won't improve it one jot," said Konstantin von Notz, the parliamentary group spokesman for the opposition Greens.
"Border controls along the Swiss border do not benefit anyone," said Ulla Jelpke, interior affairs spokesperson for the ex-communist Left party, who also accused Seehofer of espousing "dumb populism."
In contrast, the opposition far-right Alternative for Germany (AfD) party said Seehofer's plan did not go far enough.
"Not only the border with Switzerland should be protected to ensure the security of citizens," said AfD parliamentary group co-leader Alice Weidel. "An all-embracing border protection system must also be established."
Schengen drawbacks, says Ströbl
Thomas Ströbl, the interior minister of Baden-Württemberg, the German state with the longest border with Switzerland, said he agreed with Seehofer.
"Naturally, Schengen is an important achievement, but illegal border crossings must be prevented,” said Ströbl.
Last August, the Stuttgarter Zeitung newspaper quoted German federal police as saying the number of illegal entries from Switzerland into Baden-Württemberg had dropped 28% compared to the same six-month period in 2017.
Under German law, unlawful entry applies if a foreigner does not possess a required passport, a residence title, or a legitimately obtained "necessary" visa.
Mass tourism statistics
According to the federal statistics bureau (Destatis), Germany's tourism industry recorded 185 million arrivals last year, comprising both Germans on trips in their own country and foreigners.
Of these, nearly 39 million were people who had permanent residency abroad.
Bavaria with 29 million had the most arrivals, followed by Baden Württemberg with 17 million arrivals, of which 5.3 million were visitors from abroad.
ipj/amp (AFP, dpa, KNA)
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